ABOUT THE SPEAKER
Arthur Benjamin - Mathemagician
Using daring displays of algorithmic trickery, lightning calculator and number wizard Arthur Benjamin mesmerizes audiences with mathematical mystery and beauty.

Why you should listen

Arthur Benjamin makes numbers dance. In his day job, he's a professor of math at Harvey Mudd College; in his other day job, he's a "Mathemagician," taking the stage in his tuxedo to perform high-speed mental calculations, memorizations and other astounding math stunts. It's part of his drive to teach math and mental agility in interesting ways, following in the footsteps of such heroes as Martin Gardner.

Benjamin is the co-author, with Michael Shermer, of Secrets of Mental Math (which shares his secrets for rapid mental calculation), as well as the co-author of the MAA award-winning Proofs That Really Count: The Art of Combinatorial Proof. For a glimpse of his broad approach to math, see the list of research talks on his website, which seesaws between high-level math (such as his "Vandermonde's Determinant and Fibonacci SAWs," presented at MIT in 2004) and engaging math talks for the rest of us ("An Amazing Mathematical Card Trick").

More profile about the speaker
Arthur Benjamin | Speaker | TED.com
TED2005

Arthur Benjamin: A performance of "Mathemagic"

亞瑟 班傑明 表演 "數學魔術"

Filmed:
9,599,588 views

數學魔術師 亞瑟 班傑明 和一組計算機比賽算出3位數平方, 並解出一個困難的心算問題以及猜出幾個生日星期. 他是如何辦到得呢? 由他來告訴你.
- Mathemagician
Using daring displays of algorithmic trickery, lightning calculator and number wizard Arthur Benjamin mesmerizes audiences with mathematical mystery and beauty. Full bio

Double-click the English transcript below to play the video.

00:13
Well, good morning早上 ladies女士們 and gentlemen紳士.
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各位女士先生們 午安
00:14
My name名稱 is Art藝術 Benjamin本傑明, and I am a "mathemagicianmathemagician."
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我的名字是 亞瑟 班傑明, 而且我是一位"數學魔術師".
00:18
What that means手段 is, I combine結合 my loves of math數學 and magic魔法
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我結合了我的兩個最愛, 數學還有魔術
00:21
to do something I call "mathemagicsmathemagics."
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創造了我稱的 "數學魔術"
00:24
But before I get started開始, I have a quick question for the audience聽眾.
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在我開始之前, 我有一個簡單的問題
00:27
By any chance機會, did anyone任何人 happen發生
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在觀眾之中
00:29
to bring帶來 with them this morning早上 a calculator計算器?
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有沒有人剛好帶了計算機?
00:33
Seriously認真地, if you have a calculator計算器 with you, raise提高 your hand, raise提高 your hand.
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說真的, 要是你有帶計算機的話請舉手, 舉手.
00:37
I -- was -- your hand go up?
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我 - 你剛剛有舉手嗎?
00:39
Now bring帶來 it out, bring帶來 it out. Anybody任何人 else其他?
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好 拿出來, 拿出來. 還有其他人嗎?
00:41
I see, I see one way in the back.
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我看看, 我看到後方還有一位.
00:43
You sir先生, that's three,
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就是妳先生, 這樣就有三位了.
00:45
And anybody任何人 on this side here?
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在這一邊有人嗎?
00:48
OK, you over there on the aisle走道. Would the four of you with calculators計算器
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好的, 在走道邊的那一位. 請你們四位
00:50
please bring帶來 out your calculators計算器, then join加入 me up on stage階段.
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帶著你們的計算機, 帶著它們到台上.
00:53
And let's give these volunteers志願者 a nice不錯 round回合 of applause掌聲.
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請幫這些自願者鼓掌.
00:55
(Applause掌聲)
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(掌聲)
00:58
That's right. Now, since以來 I haven't沒有 had the chance機會
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沒錯. 好的, 我還沒有機會
01:01
to work with these calculators計算器, I need to make sure
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使用這些計算機, 所以我必須確定
01:04
that they are all working加工 properly正確.
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他們使用上都沒有問題.
01:06
Would somebody get us started開始 by giving us a
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有沒有人可以先給我們一個開始
01:08
two-digit兩位數 number please?
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給我一個2位數的號碼?
01:11
How about a two-digit兩位數 number?
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2位數的號碼好嗎?
01:13
Audience聽眾: 22.
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觀眾: 22
01:14
Arthur亞瑟 Benjamin本傑明: 22. And another另一個 two-digit兩位數 number, Sir先生?
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班傑明: 22. 先生, 再另一組2位數好嗎?
01:16
Audience聽眾: 47.
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觀眾: 47
01:17
ABAB: Multiply 22 times 47, make sure you get 1,034,
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班傑明: 22 乘與 47, 確定你的答案是 1,034.
01:21
or the calculators計算器 are not working加工. Do all of you get 1,034? 1,034?
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不然你的計算機就是有問題的. 你的都算到 1,034? 1,034?
01:26
Woman女人: No.
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女: 不是.
01:27
ABAB: 594. Let's give three of them a nice不錯 round回合 of applause掌聲 there.
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班傑明: 594. 我們給他們其中三位掌聲鼓勵.
01:31
(Applause掌聲)
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(掌聲)
01:33
Would you like to try a more standard標準 calculator計算器, just in case案件?
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你想不想試試一個比較標準的計算機, 以防萬一?
01:35
OK, great.
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OK, 好的.
01:37
What I'm going to try and do then --
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我現在要嘗試做的就是 --
01:39
I notice注意 that took some of you a little bit of time to get your answer回答.
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我發現你們需要滿長的一段時間來計算.
01:42
That's OK. I'll give you a shortcut捷徑 for multiplying乘以
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那沒問題. 我來教你們一個計算機
01:45
even faster更快 on the calculator計算器.
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算成法的捷徑.
01:47
There is something called the square廣場 of a number,
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一個數字的平方
01:49
which哪一個 most of you know is taking服用 a number
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你們大多都知道 就是
01:51
and multiplying乘以 it by itself本身.
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把一個數字來乘與它自己
01:53
For instance, five squared平方 would be?
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比方說, 5 的平方是?
01:55
Audience聽眾: 25.
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觀眾: 25
01:56
ABAB: 25. Now, the way we can square廣場 on most calculators計算器 --
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班傑明: 25. 現在, 我們在計算機上算平方的方式是 --
01:58
let me demonstrate演示 with this one --
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讓我用這一個來示範 --
02:00
is by taking服用 the number, such這樣 as five,
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先把一個數字, 例如 5,
02:02
hitting "times" and then "equals等於,"
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按下 "乘與" (x) 然後再按 "等於" (=),
02:05
and on most calculators計算器 that will give you the square廣場.
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然後大多數 計算器會算出平方。
02:08
On some of these ancient RPNRPN calculators計算器,
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在一些比較舊的 RPN 計算機上,
02:10
you've got an "x squared平方" button按鍵 on it,
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你會有 X^2 (X的平方) 的按鈕,
02:12
will allow允許 you to do the calculation計算 even faster更快.
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就可以更快的計算出平方.
02:15
What I'm going to try and do now is to square廣場, in my head,
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現在我要嘗試做的就是用心算
02:18
four two-digit兩位數 numbers數字
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算出四組兩位數的數字的平方
02:20
faster更快 than they can do on their calculators計算器, even using運用 the shortcut捷徑 method方法.
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比他們用計算來計算得還要快, 即使使用捷徑.
02:24
What I'll use is the second第二 row this time, and I'll get four of you --
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這次我找第二排, 請你們四位 --
02:26
one, two, three, four -- to each yell叫喊 out a two-digit兩位數 number,
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一, 二, 三, 四 -- 各喊出一組兩位數的數字,
02:29
and if you would square廣場 the first number,
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然後請你算出第一組的平方,
02:33
and if you would square廣場 the second第二, the third第三 and the fourth第四,
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再來你算出第二組的平方, 再來第三和第四,
02:35
I will try and race種族 you to the answer回答. OK?
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我試著和你們比賽看誰比較快, 好嗎?
02:38
So quickly很快, a two-digit兩位數 number please.
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快一點 -- 一組兩位數數字.
02:41
Audience聽眾: 37.
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觀眾: 37
02:42
ABAB: 37 squared平方, OK.
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班: 37 平方, OK.
02:44
Audience聽眾: 23.
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觀眾: 23
02:45
ABAB: 23 squared平方, OK.
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班: 23 平方, OK.
02:47
Audience聽眾: 59.
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觀眾: 59
02:48
ABAB: 59 squared平方, OK, and finally最後?
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班: 59 平方, OK, 再來最後
02:49
Audience聽眾: 93.
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觀眾: 93
02:51
ABAB: 93 squared平方. Would you call out your answers答案, please?
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班: 93 平方. 請你們說出你們的答案
02:54
Woman女人: 1369. ABAB: 1369.
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女: 1369 班: 1369
02:56
Woman女人: 529.
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女: 529
02:57
ABAB: 529.
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班: 529
02:58
Man: 3481.
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男: 341
02:59
ABAB: 3481.
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班: 3481
03:00
Man: 8649.
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男: 8649
03:01
ABAB: Thank you very much.
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班: 非常謝謝你們.
03:02
(Applause掌聲)
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(掌聲)
03:07
Let me try to take this one step further進一步.
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現在讓我來試著更進一步
03:10
I'm going to try to square廣場 some three-digit三位數 numbers數字 this time.
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這一次我要試著平方一些三位數
03:13
I won't慣於 even write these down --
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我甚至不把它寫下來
03:15
I'll just call them out as they're called out to me.
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我直接在數字喊出來之後說出答案
03:17
Anyone任何人 I point to, call out a three-digit三位數 number.
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我手指指到誰, 就請喊出一組三位數
03:20
Anyone任何人 on our panel面板, verify校驗 the answer回答.
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在台上的人請幫我確認我的答案
03:22
Just give some indication跡象 if it's right.
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請讓我知道我計算的是否正確
03:24
A three-digit三位數 number, sir先生, yes?
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先生, 一組三位數?
03:27
Audience聽眾: 987.
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觀眾: 987
03:28
ABAB: 987 squared平方 is 974,169.
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班: 987 平方是 974,169
03:31
(Laughter笑聲)
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(笑聲)
03:33
Yes? Good.
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對嗎? 很好
03:35
Another另一個, another另一個 three-digit三位數 --
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再來, 在一組三位數 --
03:37
(Applause掌聲)
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(掌聲)
03:38
-- another另一個 three-digit三位數 number, sir先生?
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先生, 再一組三位數?
03:41
Audience聽眾: 457.
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觀眾: 457
03:42
ABAB: 457 squared平方 is 205,849.
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班: 457 平方是 205,849
03:45
205,849?
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205,849?
03:47
Yes?
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對嗎?
03:49
OK, another另一個, another另一個 three-digit三位數 number, sir先生?
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好的, 再一組三位數?
03:52
Audience聽眾: 321.
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觀眾: 321
03:53
ABAB: 321 is 103,041. 103,041.
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班: 321 是 103,041. 103,041.
03:56
Yes? One more three-digit三位數 number please.
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對嗎? 請再多給我一組
03:59
Audience聽眾: Oh, 722.
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觀眾: 722
04:01
ABAB: 722 is 500 -- ooh, that's a harder更難 one.
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班: 722 是 500 -- 這一組比較困難
04:04
Is that 513,284?
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是 513,284 嗎?
04:07
Woman女人: Yes.
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女: 沒錯
04:08
ABAB: Yes? Oh, one more, one more three-digit三位數 number please.
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班: 對嗎? 再一組, 請再給我一組
04:11
Audience聽眾: 162.
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觀眾: 162
04:12
162 squared平方 is 26,244.
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162 平方是 26,244
04:16
Thank you very much.
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非常謝謝你們.
04:18
(Applause掌聲)
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(掌聲)
04:25
Let me try to take this one step further進一步.
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現在讓我來再進一步
04:28
(Laughter笑聲)
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(笑聲)
04:30
I'm going to try to square廣場 a four-digit四位數 number this time.
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我要試著來平方四位數的數字
04:33
Now you can all take your time on this; I will not beat擊敗 you to the answer回答 on this one,
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現在你們可以慢慢來, 我不會比你們還要快算出答案
04:36
but I will try to get the answer回答 right.
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但是我會盡量給你正確的答案
04:38
To make this a little bit more random隨機, let's take the fourth第四 row this time,
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這次為了更加隨機, 讓第四排的觀眾
04:41
let's say, one, two, three, four.
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就說.. 一, 二, 三, 四
04:44
If each of you would call out a single digit數字 between之間 zero and nine,
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你們四位一人說出一位數
04:46
that will be the four-digit四位數 number that I'll square廣場.
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組成一組四位數讓我來平方
04:49
Audience聽眾: Nine.
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觀眾: 9
04:50
ABAB: Nine.
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班: 9
04:51
Audience聽眾: Seven. ABAB: Seven.
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觀眾: 7 班: 7
04:52
Audience聽眾: Five. ABAB: Five.
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觀眾: 5 班: 5
04:53
Audience聽眾: Eight. ABAB: Eight.
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觀眾: 8 班: 8
04:55
9,758, this will take me a little bit of time, so bear with me.
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9758, 這需要一點時間
04:58
95,218,564?
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95,218,564?
05:07
Woman女人: Yes.
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女: 正確
05:08
ABAB: Thank you very much.
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班: 非常謝謝
05:10
(Applause掌聲)
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(掌聲)
05:18
Now, I would attempt嘗試 to square廣場 a five-digit五位數 number --
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現在, 讓我來平方一個五位數
05:21
and I can --
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我可以
05:23
but unfortunately不幸 most calculators計算器 cannot不能.
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但是大部分的計算機不行
05:25
(Laughter笑聲)
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(笑聲)
05:27
Eight-digit八位 capacity容量 -- don't you hate討厭 that?
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八位數的限制 -- 真是麻煩
05:30
So, since以來 we've我們已經 reached到達 the limits範圍 of our calculators計算器 --
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既然我們到了計算機的極限了 --
05:33
what's that? Does yours你的 go --
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甚麼? 你的計算機可以到幾位數?
05:36
Woman女人: I don't know.
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女: 我不知道
05:37
ABAB: Does yours你的 go higher更高?
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班: 可以超過八位數嗎?
05:39
Oh -- yours你的 does?
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你的可以嗎?
05:41
Man: I can probably大概 do it.
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男: 我的或許可以
05:42
ABAB: I'll talk to you later後來.
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班: 我晚點再跟你談談
05:44
In the meanwhile與此同時, let me conclude得出結論
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現在在第一段結束之前
05:46
the first part部分 of my show顯示 by doing something a little trickier棘手.
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讓我來用些更巧妙的把戲來小結 我的第一部 分表演。
05:49
Let's take the largest最大 number on the board here, 8649.
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讓我們用這塊板上最大的一個數字,8649。
05:52
Would you each enter輸入 that on your calculator計算器?
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你們每個人可否在計算器上輸入這個數?
05:55
And instead代替 of squaring現蕾 it this time,
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這次不要平方,
05:57
I want you to take that number and multiply it
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我要你們用那個數乘以
05:59
by any three-digit三位數 number that you want,
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任何3位數,
06:02
but don't tell me what you're multiplying乘以 by --
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但不要告訴我你所乘的數 --
06:04
just multiply it by any random隨機 three-digit三位數 number.
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只要乘以任何一個3位數。
06:07
So you should have as an answer回答 either
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那麼你得到的答案可能會是
06:09
a six-digit六位數 or probably大概 a seven-digit七位數 number.
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一個六位數或者七位數。
06:13
How many許多 digits數字 do you have, six or seven?
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你的是幾位,6還是7?
06:14
Seven, and yours你的? Woman女人: Seven.
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7,你的呢?女士:7。
06:16
ABAB: Seven? Seven?
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阿 瑟:7?7嗎?
06:19
And, uncertain不確定.
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不確定。
06:21
Man: Yeah.
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男士:是的。
06:22
ABAB: Seven. Is there any possible可能 way that I could know
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亞瑟: 7。 有沒有辦法會讓我知道
06:24
what seven digit數字 numbers數字 you have? Say "No."
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你所得到的7位數?應該不可能。
06:27
(Laughter笑聲)
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(笑聲)
06:29
Good. Then I shall attempt嘗試 the impossible不可能 --
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很好。那我應該來挑戰下這個不可能 --
06:31
or at least最小 the improbable難以置信.
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至少看上去是不太可能的事。
06:33
What I'd like each of you to do is to call out for me
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接下來我想讓你們告訴我
06:35
any six of your seven digits數字, any six of them,
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7位元數裏面的任意6位元數字。
06:38
in any order訂購 you'd like.
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任意順序都可以。
06:40
(Laughter笑聲)
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(笑聲)
06:41
One digit數字 at a time, I shall try and determine確定 the digit數字 you've left out.
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每次一位數,我會試著算出剩下的數。
06:46
So, starting開始 with your seven-digit七位數 number,
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那麼,從你開始吧。
06:48
call out any six of them please.
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請喊出任意6位元數字。
06:50
Woman女人: One, OK, 197042.
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女士:1, 哦,197042。
06:56
ABAB: Did you leave離開 out the number 6?
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亞瑟:你是不是漏說了6?
06:57
Woman女人: Yes, ABAB: Good, OK, that's one.
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女士:是的,亞瑟:很好,好的,沒錯。
06:59
You have a seven-digit七位數 number, call out any six of them please.
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你的是7位數,請大聲說出其中任意的六個數。
07:01
Woman女人: 44875.
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女 士:44875。
07:04
ABAB: I think I only heard聽說 five numbers數字. I -- wait -- 44875 --
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亞瑟: 我好像只聽到5個數位。我 -- 等下 -- 44875 --
07:09
did you leave離開 out the number 6?
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你是不是漏說了數字6?
07:11
Woman女人: Yes. ABAB: Same相同 as she did, OK. You've got a seven-digit七位數 number --
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女士:是的。 亞瑟:跟她的一樣,好的。你得到的是一個7位數 --
07:13
call out any six of them loud and clear明確.
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大聲清晰地說出其中的任意6個數字。
07:16
Man: 079044.
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男:079044.
07:20
ABAB: I think you left out the number 3?
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亞瑟:我想你漏說了數字3?
07:22
That's three. The odds可能性 of me getting得到 all four of these right by random隨機 guessing揣測
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就是3. 要是我隨便猜到話,那麼我猜中其中4位元數字的概率
07:26
would be one in 10,000: 10 to the fourth第四 power功率.
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將會是萬分之一。10的負四次方。
07:29
OK, any six of them.
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好了,任意6位元數字。
07:32
Really scramble爭奪 them up this time, please.
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這次請把它們攪亂一下。
07:34
Man: 263972.
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男:263972。
07:38
ABAB: Did you leave離開 out the number 7?
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亞瑟:你是不是漏說了數字7?
07:40
And let's give all four of these people a nice不錯 round回合 of applause掌聲.
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現在讓我們給這四位觀眾予熱烈的掌聲。
07:42
Thank you very much. (Applause掌聲)
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非常感謝。
07:52
For my next下一個 number --
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我的下一個數 --
07:54
(Laughter笑聲)
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(笑聲)
07:57
while I mentally精神上 recharge充值 my batteries電池,
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在給我腦袋充電期間
07:59
I have one more question for the audience聽眾.
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我有個問題要問下觀眾們。
08:02
By any chance機會, does anybody任何人 here happen發生 to know
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有可能的話,在場的有誰剛好知道
08:07
the day of the week that they were born天生 on?
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你生日的那天是星期幾?
08:10
If you think you know your birth分娩 day, raise提高 your hand.
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如果你覺得知道的話,舉下手。
08:14
Let's see, starting開始 with -- let's start開始 with a gentleman紳士 first,
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讓我們看看,從 -- 從男士開始,
08:17
OK sir先生, what year was it, first of all? That's why I start開始 with a gentleman紳士 first.
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好的先生, 先說下是哪一年?這就是為什麼我要先從男士開始。
08:20
What year?
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哪年?
08:21
Audience聽眾: 1953.
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觀 眾:1953。
08:22
ABAB: 1953, and the month?
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亞瑟: 1953,哪個月?
08:24
Audience聽眾: November十一月. ABAB: November十一月 what?
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觀眾:11 月。亞瑟:11月幾號?
08:25
Audience聽眾: 23rdRD.
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觀眾:23 號。
08:26
ABAB: 23rdRD -- was that a Monday星期一? Audience聽眾: Yes.
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亞瑟: 23號 -- 是不是星期一?觀眾:是的。
08:28
Yes, good. Somebody else其他? Who else其他 would like --
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沒錯,很 好。還有人嗎?還有誰想要 --
08:30
see I don't -- haven't沒有 seen看到 any women's女士的 hands up.
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呃,還沒, 我還沒看到有女士舉手。
08:32
OK, it's -- how about you, what year?
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啊,很好, 你呢,哪年?
08:34
Audience聽眾: 1949. ABAB: 1949, and the month?
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觀 眾:1949. 亞瑟: 1949, 哪月?
08:36
Audience聽眾: October十月. ABAB: October十月 what?
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觀眾: 十月。亞瑟: 十月幾號?
08:37
Audience聽眾: Fifth第五.
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觀眾: 5號。
08:38
ABAB: Fifth第五 -- was that a Wednesday星期三?
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亞瑟: 5號 -- 那是不是星期3?
08:40
Yes, my -- I'll go way to the back right now, how about you?
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沒錯,現在我從後面選,你怎樣?
08:42
Yell叫喊 it out, what year? Audience聽眾: 1959.
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大聲說出來,哪年?觀眾:1959。
08:44
ABAB: 1959, OK -- and the month?
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阿 瑟:1959, 好的 -- 哪月?
08:46
Audience聽眾: February二月.
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觀眾:二 月。
08:48
ABAB: February二月 what? Audience聽眾: Sixth第六.
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亞瑟: 2月幾號? 觀眾:6號。
08:50
ABAB: Sixth第六 -- was that a Friday星期五? Audience聽眾: Yes.
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亞瑟: 6號,那是不是星期五?觀眾:是的。
08:52
Good, how about the person behind背後 her?
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很好,在她後面的那個人要不要試試?
08:54
Call -- call -- what year was it?
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喊出 -- 哪一年?
08:56
Audience聽眾: 1947. ABAB: 1947, and the month?
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觀 眾:1947. 亞瑟: 1947,哪月?
08:58
Audience聽眾: May可能. ABAB: May可能 what?
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觀眾:5 月。亞瑟: 5月幾號?
09:00
Audience聽眾: Seventh第七. ABAB: Seventh第七 -- would that be a Wednesday星期三?
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觀眾:7 號。亞瑟:7號 -- 那是不是星期三?
09:02
Audience聽眾: Yes.
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觀眾:是的。
09:03
ABAB: Thank you very much.
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亞瑟:非常感謝。
09:05
(Applause掌聲)
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(掌聲)
09:09
Anybody任何人 here who'd誰願意 like to know the day of the week they were born天生?
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在場的哪一位想知道自己的生日是在星期幾的?
09:12
We can do it that way.
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我們也可以這麼做。
09:14
Of course課程, I could just make up an answer回答 and you wouldn't不會 know,
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當然,這樣的話我亂編一個你也不會知道,
09:16
so I come prepared準備 for that.
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所以我事先有準備了下。
09:18
I brought with me a book of calendars日曆.
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我帶了一個日曆。
09:21
It goes as far back into the past過去 as 1800, 'cause'原因 you never know.
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可以查回到1800年,誰知道會不會用得著呢?哈。
09:25
(Laughter笑聲)
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(笑聲)
09:27
I didn't mean to look at you, sir先生 --
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我不是故意看著你,先生 --
09:29
you were just sitting坐在 there.
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你只是恰巧坐在那邊。
09:31
Anyway無論如何, Chris克里斯, you can help me out here, if you wouldn't不會 mind心神.
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不管怎樣,Chris,你可以幫我下,如果你不介意的話。
09:34
This is a book of calendars日曆, and I'll ask --
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這是一本日曆,然後我會問 --
09:36
who was it that wanted to know their birth分娩 day? You sir先生? OK.
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是誰想知道他的生日的,是你嗎,先生?好的。
09:38
What year was it, first of all?
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先問下哪一 年?
09:40
Audience聽眾: 1966.
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觀 眾:1966。
09:41
ABAB: '66 -- turn to the calendar日曆 with 1966 --
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亞瑟: 66年 -- 翻到日曆的1966年 --
09:43
and what month?
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亞瑟: 哪月?
09:45
Audience聽眾: April四月. ABAB: April四月 what?
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觀眾:4 月。 亞瑟: 4月幾號?
09:47
Audience聽眾: 17th. ABAB: 17th -- I believe that was a Sunday星期日.
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觀眾:17 號。 亞瑟: 17號 -- 我確信那是個星期天。
09:50
Can you confirm確認, Chris克里斯?
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你能否確認下,Chris?
09:52
Chris克里斯 Anderson安德森: Yes. ABAB: Yeah, OK. I'll tell you what, Chris克里斯:
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Chris: 是的。亞瑟: 很好,我跟你說
09:54
as long as you have that book in front面前 of you,
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chris, 用你面前的那本書,
09:57
do me a favor偏愛, turn to a year outside of the 1900s,
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幫我下忙, 翻到1900s以外的,
10:01
either into the 1800s or way into the 2000s --
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幫我下忙, 翻到1900s以外的,
10:04
that'll那會 be a much greater更大 challenge挑戰 for me.
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翻到頁面 1800s 或者2000s --那樣對我來 說會更有挑性。
10:06
What year, Chris克里斯, would you like?
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你喜歡哪年,Chris?
10:07
CACA: 1824.
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Chris: 1824.
10:08
ABAB: 1824, OK.
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亞瑟: 1824, 好的。
10:11
And what month? CACA: June六月.
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哪月 呢?Chris: 六月。
10:13
ABAB: June六月 what? CACA: Sixth第六.
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哪月 呢?Chris: 六月
10:15
ABAB: Sixth第六 -- was that a Sunday星期日?
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6號 -- 是不是星期天?
10:17
CACA: It was. ABAB: And it was cloudy多雲的.
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Chris: 沒錯。 亞瑟:並且是陰天。
10:20
Good, thank you very much.
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很好,非常感謝。
10:22
(Applause掌聲)
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(掌聲)
10:28
But I'd like to wrap things up now
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但是現在我想來個總結
10:30
by alluding暗指 to something
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再次回到
10:33
from earlier in the presentation介紹.
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我之前的表演
10:35
There was a gentleman紳士 up here who had a 10-digit-數字 calculator計算器.
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先前臺上有位帶10位數計算器的先生。
10:38
Where is he, would you stand up,
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現在在哪裏,你能站起來一下嗎?
10:42
10-digit-數字 guy?
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10位數的夥計?
10:44
OK, well stand up for me just for a second第二,
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好的,請站 起來下,
10:47
so I can see where you are.
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好讓我可以 看到你在哪里。
10:49
OK, oh, OK -- you have a 10-digit-數字 calculator計算器, sir先生, as well?
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好,哦,好的 -- 你也有一個10位數的計算器?
10:52
OK, what I'm going to try and do, is to square廣場 in my head
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很好,我接下來要做的是,心算平方
10:56
a five-digit五位數 number requiring要求 a 10-digit-數字 calculator計算器.
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一個5位元數的數位,這需要個10位元數的計算器。
10:59
But to make my job工作 more interesting有趣 for you, as well as for me,
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為了給大家和我自己增加點樂趣,
11:04
I'm going to do this problem問題
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我會把心算過程
11:06
thinking思維 out loud.
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大聲的念出來。
11:08
So you can actually其實, honestly老老實實 hear
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這樣你們就可以實際上聽到
11:11
what's going on in my mind心神
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我心算時的具體過程
11:13
while I do a calculation計算 of this size尺寸.
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當我計算這樣大的數字的時候。
11:15
Now, I have to apologize道歉 to our magician魔術師 friend朋友 Lennart倫納特 Green綠色.
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現在,我得向我們的魔術師朋友 Lennart Green道下歉。
11:18
I know as a magician魔術師 we're not supposed應該 to reveal揭示 our secrets秘密,
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我知道作為一個魔術師本不應該洩漏我們的秘密,
11:22
but I'm not too afraid害怕 that people are going
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但我並不是很擔心其他人
11:24
to start開始 doing my show顯示 next下一個 week, so --
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會在下個星期開始模仿我的表演,所以 --
11:26
I think we're OK.
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我想沒有什麼問題。
11:30
So, let's see, let's take a --
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那麼,讓我們開始吧,
11:33
let's take a different不同 row of people, starting開始 with you.
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讓我們選另一排的觀眾,就從你開始吧。
11:35
I'll get five digits數字: one, two, three, four --
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我將得到5位數:1,2,3,4 --
11:38
oh, I did this row already已經. Let's do the row before you,
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哦,我已經選過這排了。那就選你前面的這排觀眾,
11:40
starting開始 with you sir先生: one, two, three, four, five.
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從你開始先生:1,2,3,4,5。
11:43
Call out a single digit數字 -- that will be the five-digit五位數 number
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(每個人) 喊出一個一位數 -- 這樣就組成一個5位元數的數字
11:46
that I will try to square廣場. Go ahead.
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我會心算這個數的平方。開始吧。
11:48
Audience聽眾: Five. ABAB: Five.
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觀眾:5。 亞瑟:5。
11:50
Audience聽眾: Seven. ABAB: Seven.
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觀眾:7。 亞瑟:7。
11:51
Audience聽眾: Six. ABAB: Six.
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觀眾:6。 亞瑟:6。
11:52
Audience聽眾: Eight. ABAB: Eight.
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觀眾:8。 亞瑟:8。
11:54
Audience聽眾: Three. ABAB: Three.
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觀眾:3。 亞瑟:3。
11:56
57,683
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57683
12:01
squared平方. Yuck.
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平方。慘啦。
12:03
Let me explain說明 to you how
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讓我來給大家解釋下
12:05
I'm going to attempt嘗試 this problem問題.
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我接下來要怎麼算。
12:08
I'm going to break打破 the problem問題 down into three parts部分.
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我會把這個問題分成3部分。
12:11
I'll do 57,000 squared平方,
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我先算 57000的平方,
12:13
plus 683 squared平方,
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然後加上 683的平方,
12:17
plus 57,000 times
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加上 57000乘以
12:20
683 times two.
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683乘以 2。
12:22
Add all those numbers數字 together一起,
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把所有的結果加起來,
12:24
and with any luck運氣, arrive到達 at the answer回答.
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幸運的話, 就可以得出答案。
12:28
Now, let me recap概括.
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現在,讓我先想一下(合上筆帽)。(一語雙關)
12:31
Thank you.
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謝謝。
12:34
While I explain說明 something else其他 --
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當我講一些其他的 --
12:37
-- I know, that you can use, right?
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-- 我知道,你可以利用這個,對吧?
12:40
While I do these calculation計算[s],
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當我心算的時候,在計算的過程中
12:42
you might威力 hear certain某些 words,
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你會聽到某些詞語,
12:44
as opposed反對 to numbers數字, creep爬行 into the calculation計算.
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來對應一些數字,融入到計算當中。
12:48
Let me explain說明 what that is.
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讓我來解釋下是什麼。
12:49
This is a phonetic拼音 code,
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這是語音代碼,
12:51
a mnemonic助記符 device設備 that I use,
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相當於一個記憶用的設備,
12:53
that allows允許 me to convert兌換 numbers數字 into words.
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這個設備能幫我把數字轉換成單詞。
12:56
I store商店 them as words, and later後來 on retrieve取回 them as numbers數字.
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我先存為單詞,然後再轉回成數字。
12:59
I know it sounds聲音 complicated複雜; it's not --
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我知道這聽起來有點複雜;(實際上)一點也不 --
13:01
I just don't want you to think you're seeing眼看 something out of "Rain Man" here.
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我不想讓你們以為自己看到了‘雨人’。
13:04
(Laughter笑聲)
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(笑聲)
13:06
There's definitely無疑 a method方法 to my madness瘋狂 --
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這其中絕對有種方法來解釋我瘋狂的表演 --
13:08
definitely無疑, definitely無疑. Sorry.
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一定的,一 定的。不好意思。
13:10
(Laughter笑聲)
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(笑聲)
13:14
If you want to talk to me about ADHD多動症 afterwards之後,
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如果你想找我談論小兒多動症的話,
13:16
you can talk to me then. All right --
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你可以找我談談。好吧 --
13:18
by the way, one last instruction指令,
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順便提下,
13:20
for my judges法官 with the calculators計算器 -- OK, you know who you are --
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給我那個有計算器的裁判最後一個說明
13:23
there is at least最小 a 50 percent百分 chance機會
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至少有一半的機會
13:26
that I will make a mistake錯誤 here.
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我會犯錯。
13:29
If I do, don't tell me what the mistake錯誤 is;
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如果算錯了,不要告訴我哪里錯了;
13:32
just say, "you're close," or something like that, and I'll try and figure數字 out the answer回答 --
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只要說, ‘接近了,’或者類似的,然後我會再試著算出正確的答案 --
13:35
which哪一個 could be pretty漂亮 entertaining娛樂 in itself本身.
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這樣會更有趣點。
13:39
If, however然而, I am right,
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如果,我對了的話,
13:41
whatever隨你 you do, don't keep it to yourself你自己, OK?
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無論如何, 你都不要自己留著結果,好嗎?
13:44
(Laughter笑聲)
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(笑聲)
13:45
Make sure everybody每個人 knows知道 that I got the answer回答 right,
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確保讓大家知道我算對了,
13:47
because this is my big finish, OK.
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因為這對我來說是個完美的收場。
13:50
So, without any more stalling失速,
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好吧,閒話少說,
13:53
here we go.
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我們開始吧。
13:56
I'll start開始 the problem問題 in the middle中間, with 57 times 683.
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我會從問題的中間部分開始,先算57乘以683。
13:58
Now, 57 times 68 is 3,400, plus 476 is 3876,
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現在,57乘以68等於3400,加上476等於3876,
14:01
that's 38,760 plus 171,
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那是 38760加上171,
14:04
38,760 plus 171 is 38,931.
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38760 加上171等於38931。
14:07
38,931; double that to get 77,862.
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38931; 翻一倍得到77862。
14:11
77,862 becomes cookie曲奇餅 fission分裂,
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77862 變成‘cookie fission’,
14:13
cookie曲奇餅 fission分裂 is 77,822.
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‘cookie fission’ 是77822。
14:17
That seems似乎 right, I'll go on. Cookie曲奇餅 fission分裂, OK.
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好像沒錯, 繼續。'cookie fission’,好的。
14:19
Next下一個, I do 57 squared平方, which哪一個 is 3,249, so I can say,
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接下來,我算57的平方等於3249,那麼應該是,
14:23
three billion十億. Take the 249, add that to cookie曲奇餅, 249,
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30億。用249加上'cookie',249,
14:28
oops哎呀, but I see a carry攜帶 coming未來 --
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哦,但是我看到有一個包過來了 --
14:30
249 --
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249 --
14:32
add that to cookie曲奇餅, 250 plus 77,
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加上 'cookie',250加上77,
14:34
is 327 million百萬 --
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等於3億2千7百萬 --
14:38
fission分裂, fission分裂, OK, finally最後, we do 683 squared平方,
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'fission, fission,' 好的,總算可以算683的平方了,
14:41
that's 700 times 666, plus 17 squared平方
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相當於 700乘以666,再加上17的平方
14:43
is 466,489, rev up if I need it,
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等於 466489,我需要的時候轉起來,
14:46
rev up, take the 466,
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放大,用 466,
14:48
add that to fission分裂, to get,
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加上 'fission',得到,
14:50
oh gee哎呀 --
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哦老天 --
14:54
328,489.
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328489。
14:58
Audience聽眾: Yeah!
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觀眾:沒錯!
14:59
ABAB: Good.
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亞瑟:很好。
15:00
(Applause掌聲)
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(掌聲)
15:01
Thank you very much.
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非常感謝。
15:03
I hope希望 you enjoyed享受 mathemagicsmathemagics. Thank you.
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希望你們能喜歡數學魔術。謝謝大家。
15:05
(Applause掌聲)
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(掌聲)
Translated by Wang Qian
Reviewed by Zachary Lin Zhao

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ABOUT THE SPEAKER
Arthur Benjamin - Mathemagician
Using daring displays of algorithmic trickery, lightning calculator and number wizard Arthur Benjamin mesmerizes audiences with mathematical mystery and beauty.

Why you should listen

Arthur Benjamin makes numbers dance. In his day job, he's a professor of math at Harvey Mudd College; in his other day job, he's a "Mathemagician," taking the stage in his tuxedo to perform high-speed mental calculations, memorizations and other astounding math stunts. It's part of his drive to teach math and mental agility in interesting ways, following in the footsteps of such heroes as Martin Gardner.

Benjamin is the co-author, with Michael Shermer, of Secrets of Mental Math (which shares his secrets for rapid mental calculation), as well as the co-author of the MAA award-winning Proofs That Really Count: The Art of Combinatorial Proof. For a glimpse of his broad approach to math, see the list of research talks on his website, which seesaws between high-level math (such as his "Vandermonde's Determinant and Fibonacci SAWs," presented at MIT in 2004) and engaging math talks for the rest of us ("An Amazing Mathematical Card Trick").

More profile about the speaker
Arthur Benjamin | Speaker | TED.com