problem solving

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problem solving

by suryapal » Wed Mar 10, 2010 6:37 am
Q. The number 75 can be written as the sum of the square of three different positive integers.what is the sum of these 3 integers?

ans. 13

please explain....
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by seanceserene » Wed Mar 10, 2010 7:08 am
suryapal wrote:Q. The number 75 can be written as the sum of the square of three different positive integers.what is the sum of these 3 integers?

ans. 13

please explain....
considering 75 is not a big number, i list all the possible square of a positive integer

1^2=1
2^2=4
3^2=9
4^2=16
5^2=25
6^2=36
7^2=49
8^2=64

and i get 49+25+1=75, 7+5+1=13

hope this helps'
it is not an "alice in wonderland". it is real! i am going to freak GMAT out!