offers hundreds of practice questions and video explanations. Go there now.

# Practice Question of the Week #2: Win a Premium Subscription to Magoosh GRE!

Integer properties:

If is an non-negative integer and is a divisor of then =

A.
B.
C.
D.
E.

The answer will be posted tomorrow afternoon, and we’ll be choosing another winner to receive a free premium subscription to the Magoosh GRE product to help you study!

Submit a correct answer and explanation by commenting on this post or head over to our facebook with your response before 1PM Pacific Daylight Time tomorrow and we will select any one of the readers with the correct answer to win.

This is a pretty touch challenge problem, good luck!

EDIT: Comments will remain hidden until we release the answer and the name of the winner, so don’t worry– if you submitted an answer with an explanation, we can see it, even if it may not show up on the post for you!

By the way, students who use Magoosh GRE improve their scores by an average of 8 points on the new scale (150 points on the old scale.) Click here to learn more.

### 4 Responses to Practice Question of the Week #2: Win a Premium Subscription to Magoosh GRE!

1. Ashok Kumar June 8, 2011 at 10:57 am #

(B) 1

Explanation:

For divisibility by 15, the number should be divisible by both 3 and 5.
Checking divisibility by 3, we find that it is not divisible. Because 7 + 5 + 9 + 3 + 2 + 5 = 31 which is not divisible by 3. Hence 15 or any multiple of 15 cannot divide that number exactly. Hence the only possible solution is k = 0.

If k = 0, then 3^0 – 0^3 => 1 – 0 => 1

• margarette June 8, 2011 at 2:55 pm #

Ashok, I just sent you an e-mail that explains how to claim your prize. Congrats!

2. Nirav June 7, 2011 at 11:15 am #

As 15 is not a divisor of 759325, neither are any powers of 15.
Therefore k is 0. 15^1 is 1, which is a divisor of 759325.
3^0 – 0^3 = 1

3. Karthik Chockkalingam June 7, 2011 at 11:05 am #

Ans is 1.
15 Power 1 is 15 and it is not a divisor of the given number.And hence the higher power of 15 will not be a divisor of the given number. For instance, If we take 15 power 5, the value is 759,375.
Therefore the only possibility is 15 Power 0 is 1 and we know that 1 is a divisor for all the numbers. The value of K is 0.
Substituting this, we have (3^0)-(0^3) ans it is simplified as 1-0=1. Hence the solution is arrived.

Magoosh blog comment policy: To create the best experience for our readers, we will only approve comments that are relevant to the article, general enough to be helpful to other students, concise, and well-written! 😄 Due to the high volume of comments across all of our blogs, we cannot promise that all comments will receive responses from our instructors.

We highly encourage students to help each other out and respond to other students' comments if you can!

If you are a Premium Magoosh student and would like more personalized service from our instructors, you can use the Help tab on the Magoosh dashboard. Thanks!