# Simple math problem.
**URL:** https://boards.straightdope.com/t/simple-math-problem/318692
**Category:** Miscellaneous and Personal Stuff I Must Share
**Created:** [August 26, 2005, 4:09am UTC](https://boards.straightdope.com/t/simple-math-problem/318692 "2005-08-26T04:09:54Z")
**Posts on this page:** 20
**Page:** 1
### Author:  [@Idle\_Thoughts](https://boards.straightdope.com/u/Idle_Thoughts)
#### Post date: [August 26, 2005, 4:09am UTC](https://boards.straightdope.com/t/simple-math-problem/318692/1 "2005-08-26T04:09:54Z")
See if you can get the answer.
Please keep your scroll bar right here, though…as in, don’t scroll down and read anyone’s reply yet. See if you can do it yourself.
Also, don’t use a calculator or Pen/Pencil and paper. It’s easy enough to do in your head.
You start out with 1000.
Add 40.
Add another 1000.
Add 30.
Add another 1000
Add 20.
Add another 1000.
And finally, you add 10.
What number did you get? Reply first by hitting the submit reply at the TOP of this thread,…THEN read your fellow doper’s replies and comments.
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### Author:  [@Gangster\_Octopus](https://boards.straightdope.com/u/Gangster_Octopus)
#### Post date: [August 26, 2005, 4:23am UTC](https://boards.straightdope.com/t/simple-math-problem/318692/2 "2005-08-26T04:23:44Z")
4100
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### Author:  [@Cunctator](https://boards.straightdope.com/u/Cunctator)
#### Post date: [August 26, 2005, 4:28am UTC](https://boards.straightdope.com/t/simple-math-problem/318692/3 "2005-08-26T04:28:55Z")
4100
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### Author:  [@What\_Exit](https://boards.straightdope.com/u/What_Exit)
#### Post date: [August 26, 2005, 4:44am UTC](https://boards.straightdope.com/t/simple-math-problem/318692/4 "2005-08-26T04:44:24Z")
4100
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### Author:  [@Jayn\_Newell](https://boards.straightdope.com/u/Jayn_Newell)
#### Post date: [August 26, 2005, 5:06am UTC](https://boards.straightdope.com/t/simple-math-problem/318692/5 "2005-08-26T05:06:29Z")
1. I will admit, I almost got tricked.
(hasn’t read responses yet)
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### Author:  [@Civil\_Guy](https://boards.straightdope.com/u/Civil_Guy)
#### Post date: [August 26, 2005, 5:29am UTC](https://boards.straightdope.com/t/simple-math-problem/318692/6 "2005-08-26T05:29:41Z")
4100
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### Author:  [@Eonwe](https://boards.straightdope.com/u/Eonwe)
#### Post date: [August 26, 2005, 5:38am UTC](https://boards.straightdope.com/t/simple-math-problem/318692/7 "2005-08-26T05:38:35Z")
I got 4100… what’s the trick?
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### Author:  [@Idle\_Thoughts](https://boards.straightdope.com/u/Idle_Thoughts)
#### Post date: [August 26, 2005, 5:55am UTC](https://boards.straightdope.com/t/simple-math-problem/318692/8 "2005-08-26T05:55:37Z")
> [@Jayn\_Newell](#):
>
> 1. I will admit, I almost got tricked.
>
> (hasn’t read responses yet)
I got did the mistake not once but twice before. :smack:
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### Author:  [@Idle\_Thoughts](https://boards.straightdope.com/u/Idle_Thoughts)
#### Post date: [August 26, 2005, 5:58am UTC](https://boards.straightdope.com/t/simple-math-problem/318692/9 "2005-08-26T05:58:31Z")
> [@Eonwe](#):
>
> I got 4100… what’s the trick?
A lot of people get 5000 if they do it all in their head.
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### Author:  [@LVgeogeek](https://boards.straightdope.com/u/LVgeogeek)
#### Post date: [August 26, 2005, 6:24am UTC](https://boards.straightdope.com/t/simple-math-problem/318692/10 "2005-08-26T06:24:58Z")
I get 4100.
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### Author:  [@EllisDee](https://boards.straightdope.com/u/EllisDee)
#### Post date: [August 26, 2005, 6:30am UTC](https://boards.straightdope.com/t/simple-math-problem/318692/11 "2005-08-26T06:30:15Z")
It’s more effective if done verbally. You can _see_ four 1000s on the screen, and no other big numbers, so it is painfully obvious it will be just over 4000. When you do the same thing out loud, more people will make the mistake intended by this riddle.
One way to simulate this effect might be with spoilers:
You start out with 1000.[/spoiler]Add 40.Add another 1000.Add 30.Add another 1000Add 20.Add another 1000.[spoiler]And finally, you add 10.
But GODDAMN that’s ugly and annoying on the eyes.
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### Author:  [@BadBadger](https://boards.straightdope.com/u/BadBadger)
#### Post date: [August 26, 2005, 8:12am UTC](https://boards.straightdope.com/t/simple-math-problem/318692/12 "2005-08-26T08:12:47Z")
Initially I went 5000. But then I thought, come on there must be something up here. Thought you may be “adding another” to a seperate column as it were. Got 4000 vs 100. That’s when I saw my mistake. Very nice illustration **Idle**
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### Author:  [@What\_Exit](https://boards.straightdope.com/u/What_Exit)
#### Post date: [August 26, 2005, 12:26pm UTC](https://boards.straightdope.com/t/simple-math-problem/318692/13 "2005-08-26T12:26:58Z")
I think it only works well verbally. The fact I could see the numbers alllowed me to quickly add the 4 1000’s and then the small numbers.
If read out loud to someone the chance of getting the 5000 answer is much higher.
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### Author:  [@Clothahump](https://boards.straightdope.com/u/Clothahump)
#### Post date: [August 26, 2005, 2:58pm UTC](https://boards.straightdope.com/t/simple-math-problem/318692/14 "2005-08-26T14:58:57Z")
I came up with 4100.
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### Author:  [@Zebra](https://boards.straightdope.com/u/Zebra)
#### Post date: [August 26, 2005, 3:35pm UTC](https://boards.straightdope.com/t/simple-math-problem/318692/15 "2005-08-26T15:35:52Z")
I fell for it. It took me a while to figure out what I did wrong.
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### Author:  [@ILovCoffee](https://boards.straightdope.com/u/ILovCoffee)
#### Post date: [August 26, 2005, 4:42pm UTC](https://boards.straightdope.com/t/simple-math-problem/318692/16 "2005-08-26T16:42:18Z")
4100
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### Author:  [@Kythereia](https://boards.straightdope.com/u/Kythereia)
#### Post date: [August 26, 2005, 4:45pm UTC](https://boards.straightdope.com/t/simple-math-problem/318692/17 "2005-08-26T16:45:28Z")
All right, I’m stupid, I keep getting 5000. _stalks off, :o_
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### Author:  [@ILovCoffee](https://boards.straightdope.com/u/ILovCoffee)
#### Post date: [August 26, 2005, 4:45pm UTC](https://boards.straightdope.com/t/simple-math-problem/318692/18 "2005-08-26T16:45:38Z")
Idle Thoughts, what is the correct answer?
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### Author:  [@Shagnasty](https://boards.straightdope.com/u/Shagnasty)
#### Post date: [August 26, 2005, 4:51pm UTC](https://boards.straightdope.com/t/simple-math-problem/318692/19 "2005-08-26T16:51:47Z")
I fell for it too. I even fell for it after I knew the right answer. Pretty good trick for the dense.
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### Author:  [@Hal\_Briston](https://boards.straightdope.com/u/Hal_Briston)
#### Post date: [August 26, 2005, 5:28pm UTC](https://boards.straightdope.com/t/simple-math-problem/318692/20 "2005-08-26T17:28:51Z")
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4100? I think the hook here might be that 4090 + 10 will trick people into answering 5000.
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