Difficult Math Question #52 - Algebra

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Difficult Math Question #52 - Algebra

by 800guy » Mon Nov 13, 2006 4:59 pm
If k=m(m+4)(m+5) k and m are positive integers. Which of the following could divide k evenly?

I.3
II.4
III.6

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Re: Difficult Math Question #52 - Algebra

by kulksnikhil » Tue Nov 14, 2006 10:59 pm
800guy wrote:If k=m(m+4)(m+5) k and m are positive integers. Which of the following could divide k evenly?

I.3
II.4
III.6
Guess this is not complete question...

aren't there combinations like I only, I & II etc ??

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OA

by 800guy » Wed Nov 15, 2006 5:32 pm
you're right, kulksnikhil. this problem wasn't given in complete form. anyway, here's the OA:

The idea is to find what are the common factors that we get in the answer.

m = 1, k = 30 which is divisible by 1,2,3,5,6,10, 15 and 30
m = 2, k = 84 which is divisible by 1,2,3,4,6, ....

As can be seen, the common factors are 1,2,3,6

So answer is 3 and 6