If n is a multiple of 5 and n = p^2 * q, where p and q are prime, then p OR q is 5.
Say that n = 2^2 x 5 = 20 OR 5^2 x 2 = 50
A) p could be either 5 or another prime number. Eliminate.
B)q could be either 5 or another prime number. Eliminate.
C) 2 x 5 = 10. Eliminate.
D) 2 x 2 x 5 x 5 = 4 x 25 = 100. You have chosen the lowest possible prime number to accompany 5, and this gave you a multiple of 25. This could be the answer.
E) Again 2 x 2 x 2 x 5 = 40. Not a multiple of 25.
Choose D.
gmat prep test 2-Multiples
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AleksandrM
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