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shreyas.rf
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Factors

by shreyas.rf Wed Aug 14, 2013 11:32 pm

If p is a positive integer less than 75 and 3p/84 is an integer,
then p has how many di§erent positive prime factors?
Jazmet
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Re: Factors

by Jazmet Thu Aug 15, 2013 6:55 am

Since 3p/84 is an integer, it states that 3p is divisible by all the prime factors of 84. (for example - 8/4 - 8 has all the prime factors of 4 and including their powers) - hence we need to break down 84 - 2 x 2 x 3 x 7.

Since 3 is already mentioned in the numerator, 'P' is bound to have all the remaining primes with their powers. So, 'P' has two more prime factors i.e. 2 and 7.

Hence the answer is two.
jnelson0612
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Re: Factors

by jnelson0612 Thu Aug 15, 2013 10:29 pm

Excellent work, Jazmet!

What is the original source of this question?
Jamie Nelson
ManhattanGMAT Instructor