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OG 13 204

by oquiella » Wed Dec 23, 2015 4:33 pm
If n=4p, where p is a prime number greater than 2 how many different positive even divisors does n have, including n?


A. Two
B. Three
C. Four
D. Six
E. Eight


Answer: C


Please explain for dummies :-(...Mind boggled

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by Brent@GMATPrepNow » Thu Dec 24, 2015 6:43 am
If n=4p where p is a prime number greater than 2, how many different positive even divisors does n have including n?

A. Two
B. Three
C. Four
D. Six
E. Eight
Let's pick a possible value for n.
To do so, let p=3 (a prime greater than 2), which means n = 4(3) = 12
The even divisors of 12 are 2, 4, 6 and 12
So, there are four even divisors.
Answer = C

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by [email protected] » Thu Dec 24, 2015 9:19 am
Hi oquiella,

This question can be solved rather easily by TESTing VALUES:

We're told that N = 4P and that P is a prime number greater than 2. Let's TEST P = 3; so N = 12

The question now asks how many DIFFERENT positive EVEN divisors does 12 have, including 12?

12:
1,12
2,6
3,4

How many of these divisors are EVEN? 2, 4, 6, 12 .....4 even divisors.

Final Answer: C

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