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

Redeem

The ratio of the number of boys to the number of girls in

This topic has expert replies
Post new topic Post Reply
Previous Topic Next Topic
Moderator
Posts: 2599
Joined: Sun Oct 29, 2017 2:08 pm
Followed by:2 members

The ratio of the number of boys to the number of girls in

by AAPL » Sat Jul 20, 2019 6:55 am

Timer

00:00

Your Answer

A

B

C

D

E

Global Stats

Economist GMAT

The ratio of the number of boys to the number of girls in Washington High School is 5:3. What is the number of teachers in the school?

1) In the same school, the ratio of the number of girls to the number of teachers is 4:17.
2) There are less than 55 teachers in the school.

OA C
Top
Source: — Data Sufficiency |
Legendary Member
Posts: 2499
Joined: Sun Oct 29, 2017 2:04 pm
Followed by:6 members

by swerve » Sat Jul 20, 2019 11:06 am

Timer

00:00

Your Answer

A

B

C

D

E

Global Stats

Boys:Girls = 5:3.

1) In the same school, the ratio of the number of girls to the number of teachers is 4:17.

Girls:Teachers = 4:17 = 12:51;
Boys:Girls = 5:3 = 20:12 (from the stem).

Boys:Girls:Teachers = 20:12:51. So, we know that the number of teachers must be a multiple of 51. Not sufficient.

2) There are less than 55 teachers in the school. Clearly insufficient.

1)+2) The least positive multiple of 51 less than 55 is 51, thus there are 51 teachers. Sufficient.

Therefore, the correct answer is __C__.
Top
Post new topic Post Reply
• Page 1 of 1