some of integers

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some of integers

by Atult718 » Wed Aug 01, 2007 1:28 am
another one
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by erdnah » Wed Aug 01, 2007 2:20 am
the primes are 5, 5 and 3. their sum is 13.

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by givemeanid » Wed Aug 01, 2007 6:18 am
3 DIFFERENT positive integers. So, it cannot be 25+25+25

75 = 49 + 25 + 1 = 7^2 + 5^2 + 1^2

Sum = 7+5+1 = 13
So It Goes

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by agps » Mon Aug 20, 2007 3:43 pm
all you know is that
z^2+y^2+x^2=75
and z,y and x are different positive integers.

factorize 75
75 = 3*25 = 3*5*5*1 (when factorizing don't forget *1 is always possible)

so 1,3 and 5 are candidates, but
1^2+3^2+5^2=35

so try combinations
3^2+5^2+x^2 =75
x^2=41, not possible

3^2+1^2+x^2=75
x^2=65, not possible

1^2+5^2+x^2=75
x^2=49, possible for
x=7 or x=-7
but x is a positive integer so x=7

7+5+1=13