Let have a Test:

You need to make a calculation. Please do neither use a calculator nor a paper. Calculate everything “in your brain”.

Take 1000

and add 40.

Now, add another 1000.

Now add 30.

Now, add 1000 again.

Add 20.

And add 1000 again.

And an additional 10.


So, You Got The RESULT! 

Quicker you see the answer, sharper you are!

    1. Ha ha! When counting by head, one can make these kind of mistakes. Ask any math frequent buddy, you’ll probably get the same answer. Key point of this test is the last step: Four thousands and Ninety plus Ten equals what? : Five Thousand 😉

  1. I got 4100 after reading it, but if I had heard it, I would’ve probably gotten 5000.
    Why: I saw four 1000’s and a group of four other numbers that I knew added up to 100, so I thought 4*1000 + 100. If I had heard it, the numbers would have been added in order (incorrectly) and I wouldn’t have been able to do this weird visual thing I do with numbers.

    this mean that you’re a genius! Congrats!—[Gaurav]

  2. I got 3100….

    You said take a thousand so I instantly thought to subtract a 1000 from zero to start off with making it -1000

    Plus 40 makes it -960

    Plus 1000 makes it 1040.

    Add 30 makes it 1070

    Add 1000 makes it 2070

    Add 20 makes it 2090

    Add 1000 makes it 3090

    Add 10 makes it 3100.

  3. Fool me once shame on you, fool me twice shame om me.
    I have had this puzzle before, so this time I got theright answer.

  4. The calculation can’t possibly start by taking away a thousand, because two lines later, it states “add ANOTHER 1,000.” In order to add “another” 1000, there had to have been a first 1000. We know the first 1,000 is a positive number for two reasons: 1) There’s no minus sign in front of it, nor any mention of a negative, and 2) “Take” is an instruction to receive something, so we know we have received 1,000 with which to start the calculation. “Take away” would be the instruction to subtract.

    I got the right answer, but did the math visually. I couldn’t help it, when I looked at the whole, the numbers added themselves. If that doesn’t happen, I easily get mired in the muck of mathematical “logic.” 🙂

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