GMAT Practice Question (Answer)
September 17th, 2008
Yesterday, we posted a 700+ level GMAT question. Below is the answer and explanation. How’d you do?
Answer: C
To be a perfect square, you must be able to take the square root of Q. Practically, that means both x and y need to be even numbers.
Statement 1: We learn that Q has at least 4 3’s and 2 7’s in its prime factors, but we don’t know there aren’t more than that. Q could have 5 3’s, which case y would be 5 and you would not be able to square root Q.
Statement 2: Since 243 is 35 and 343 is 73, Q has less than 5 3’s, and less than 3 7’s in its prime factors. But again, y could be any number less than 5 and x any number less than 3, even or odd.
Together – Q has exactly 4 3’s and 2 7’s in its prime factors and is therefore a square of an integer.
Entry Filed under: GMAT Practice Questions
WordPress database error: [Can't find file: 'wp_comments' (errno: 2)]
SELECT * FROM wp_comments WHERE comment_post_ID = '109' AND comment_approved = '1' ORDER BY comment_date
Leave a Comment
Some HTML allowed:
<a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <code> <em> <i> <strike> <strong>
Trackback this post | Subscribe to the comments via RSS Feed