If 37.5% of the 880 students at a certain college are enrolled in biology classes, how many students at the college are NOT enrolled in a biology class?
A. 110
B. 330
C. 550
D. 430
E. 880
The OA is C.
Please, can any expert explain this PS question for me? I tried to solve it but I can't get the correct answer. I need your help. Thanks.
If 37.5% of the 880 students at a certain college...
This topic has expert replies
GMAT/MBA Expert
- Brent@GMATPrepNow
- GMAT Instructor
- Posts: 16207
- Joined: Mon Dec 08, 2008 6:26 pm
- Location: Vancouver, BC
- Thanked: 5254 times
- Followed by:1268 members
- GMAT Score:770
37.5% = 3/8swerve wrote:If 37.5% of the 880 students at a certain college are enrolled in biology classes, how many students at the college are NOT enrolled in a biology class?
A. 110
B. 330
C. 550
D. 430
E. 880
So, we can say: 3/8 of the 880 students at a certain college ARE enrolled in biology classes
This means 5/8 of the 880 students at a certain college are NOT enrolled in biology classes
5/8 of 880 = (5/8)(880) = 550
Answer: C
Cheers,
Brent
GMAT/MBA Expert
- Brent@GMATPrepNow
- GMAT Instructor
- Posts: 16207
- Joined: Mon Dec 08, 2008 6:26 pm
- Location: Vancouver, BC
- Thanked: 5254 times
- Followed by:1268 members
- GMAT Score:770
We can actually solve this question without doing any calculations. Instead, we'll just use a little number sense.swerve wrote:If 37.5% of the 880 students at a certain college are enrolled in biology classes, how many students at the college are NOT enrolled in a biology class?
A. 110
B. 330
C. 550
D. 430
E. 880
37.5% is less than 1/2.
So, if LESS THAN half of the 880 students ARE enrolled in biology, we can conclude that MORE THAN half of the 880 students are NOT enrolled in biology.
Half of 880 is 440, so we're looking for an answer choice that's GREATER THAN 440
This leaves C or E.
Of course, E makes no sense, so the correct answer must be C
Cheers,
Brent
GMAT/MBA Expert
- [email protected]
- Elite Legendary Member
- Posts: 10392
- Joined: Sun Jun 23, 2013 6:38 pm
- Location: Palo Alto, CA
- Thanked: 2867 times
- Followed by:511 members
- GMAT Score:800
Hi swerve,
We're told that 37.5% of the 880 students at a certain college are enrolled in biology classes. We're asked for the number of students at the college are NOT enrolled in a biology class. The answer choices to this question are 'spread out' enough that we can answer it with estimation.
37.5% can be 'rounded' to 1/3
880 can be 'rounded' to 900
1/3 of 900 is 300, so approximately 300 of the students are enrolled in biology classes. This means that 880 - 300 = 580 are NOT enrolled in biology classes. There's only one answer that's close to 580...
Final Answer: C
GMAT assassins aren't born, they're made,
Rich
We're told that 37.5% of the 880 students at a certain college are enrolled in biology classes. We're asked for the number of students at the college are NOT enrolled in a biology class. The answer choices to this question are 'spread out' enough that we can answer it with estimation.
37.5% can be 'rounded' to 1/3
880 can be 'rounded' to 900
1/3 of 900 is 300, so approximately 300 of the students are enrolled in biology classes. This means that 880 - 300 = 580 are NOT enrolled in biology classes. There's only one answer that's close to 580...
Final Answer: C
GMAT assassins aren't born, they're made,
Rich
GMAT/MBA Expert
- Scott@TargetTestPrep
- GMAT Instructor
- Posts: 7249
- Joined: Sat Apr 25, 2015 10:56 am
- Location: Los Angeles, CA
- Thanked: 43 times
- Followed by:29 members
Since 37.5% = 3/8, 3/8 of the 880 students are enrolled in biology classes. That means 5/8 of the students or 5/8 x 880 = 5 x 110 = 550 students are not.swerve wrote:If 37.5% of the 880 students at a certain college are enrolled in biology classes, how many students at the college are NOT enrolled in a biology class?
A. 110
B. 330
C. 550
D. 430
E. 880
The OA is C.
Please, can any expert explain this PS question for me? I tried to solve it but I can't get the correct answer. I need your help. Thanks.
Answer: C
Scott Woodbury-Stewart
Founder and CEO
[email protected]
See why Target Test Prep is rated 5 out of 5 stars on BEAT the GMAT. Read our reviews