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!

Total
0
Shares


Feel free to ask questions, send feedback and even point out mistakes. Great conversations start with just a single word. How to write better comments?
13 comments
    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.” 🙂

Leave a Reply

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.

You May Also Like
calculator
Read More

Essential Steps of Problem Solving in Mathematical Sciences

Learning how to solve problems in mathematics is simply to know what to look for.   Mathematics problems often require established procedures. To become a problem solver, one must know What, When and How to apply them. To identify procedures, you have to be familiar with the different problem situations. You must also be good in gathering information, extracting strategies…

A Problem On Several Triangles

A triangle $ T $ is divided into smaller triangles such that any two of the smaller triangles either have no point in common, or have a vertex in common, or actually have an edge in common. Thus no two smaller triangles touch along part of an edge of them. For an illustration let me denote the three vertices of…
games ideas.jpg
Read More

2014 – Most Googled Games in Indian States

The folks from coupon sharing website CouponDaddy.in have created an interesting infographic featuring the list of games that were Googled most in different states of the country. The image below is the result of their statistical analysis of Google Search by Indian users for gaming specific keywords. It enlists 33 games from 33 Indian states & union territories. See which…
Read More

Solving Ramanujan’s Puzzling Problem

Consider a sequence of functions as follows:- $ f_1 (x) = \sqrt {1+\sqrt {x} } $ $ f_2 (x) = \sqrt{1+ \sqrt {1+2 \sqrt {x} } } $ $ f_3 (x) = \sqrt {1+ \sqrt {1+2 \sqrt {1+3 \sqrt {x} } } } $ ……and so on to $ f_n (x) = \sqrt {1+\sqrt{1+2 \sqrt {1+3 \sqrt {\ldots \sqrt {1+n…
Read More

The Area of a Disk

If you are aware of elementary facts of geometry, then you might know that the area of a disk with radius $ R$ is $ \pi R^2$ . The radius is actually the measure(length) of a line joining the center of disk and any point on the circumference of the disk or any other circular lamina. Radius for a disk…