Two Digit Numbers
Math brain teasers require computations to solve.
Take the 2-digit number 45.
Square it (45 x 45) to make 2025
Split this 4-digit number in half to make 20 and 25
Add them (20 + 25) to make 45
Which is what you started with.
Can you find another 2-digit number which does the same?
Comments
Piffle 
Jul 09, 2002
| This is a good one, I think. Good job. |
peppermintwist
Jul 09, 2002
| Clever! |
george1978
Jul 12, 2002
| i liked this one |
rufio
Aug 21, 2002
| "Can you find another 2-digit number which does the same?" The correct answer, in my case, was "No." TECHNICALLY, it was the right answer. |
Smithy 
Aug 20, 2003
| d'oh. Rufio - I was gonna say that. You beat me to it by about a year. Except I was gonna say yes. |
lessthanjake789
Oct 14, 2006
| no one has commented in just about forever on this teaser. clever and tough. id be surprised if you figured that out all on your own, unless you have a system for it. id be interested to hear it actually. if its just a fact then - now i know, and thanks! |
Jimbo
May 11, 2009
| It's easily done with a spreadsheet but if you try it algebraically, it is hard to deal with the bit where you split the number in half. This step has a fraction in it which can be removed in a spreadsheet by the 'Round Down' function but it is much more difficult to deal with the remainder in Algebra.
I believe that teasers like this belong in the 'Trivia' category unless you accept that creating a spreadsheet is a legitimate way to solve Mathematical teasers.  |
c0forerunner0
Feb 18, 2013
| How about 10?
Take the 2-digit number 10.
Square it to make 100
Split this number to make 10 and 0
Add them to make 10
Which is what you started with. |
spikethru4
Feb 18, 2013
| Well, if you split 100 according to the rules, you'd end up with 01 and 00, which sums to 1, so no. |
Back to Top
| |
|
