Query on an OG question

BREAKING: Target Test Prep releases Brand New 2026 On Demand GMAT prep course

Redeem

This topic has expert replies

Post new topic Post Reply

Previous Topic Next Topic

knight247: Legendary Member; Posts: 504; Joined: Tue Apr 19, 2011 1:40 pm; Thanked: 114 times; Followed by:11 members

Query on an OG question

by knight247 » Wed Aug 10, 2011 3:47 am

If n is a positive integer and k=5.1*10^9, what is the value of k?
(1)6000<k<500,000
(2)kÂ²=2.601*10^9

I've figured the answer is D. Pretty straight forward problem.I have a bit of a silly question though. I just wanna know why in statement 2,we don't consider k=Â±âˆš(2.601*10^9)? thereby making this statement insufficient.

Quote

Source: Beat The GMAT — Problem Solving | Wed Aug 10, 2011 3:47 am

GMAT/MBA Expert

Anurag@Gurome: GMAT Instructor; Posts: 3835; Joined: Fri Apr 02, 2010 10:00 pm; Location: Milpitas, CA; Thanked: 1854 times; Followed by:523 members; GMAT Score:770

by Anurag@Gurome » Wed Aug 10, 2011 3:53 am

knight247 wrote:If n is a positive integer and k=5.1*10^9, what is the value of k?
(1)6000<k<500,000
(2)kÂ²=2.601*10^9

I've figured the answer is D. Pretty straight forward problem.I have a bit of a silly question though. I just wanna know why in statement 2,we don't consider k=Â±âˆš(2.601*10^9)? thereby making this statement insufficient.

Because either in this question k = 5.1*10^9 or in the original question k = 5.1*10^n, which makes k a positive integer.