A total of 45 male and female students take a math test. The

This topic has expert replies
User avatar
Elite Legendary Member
Posts: 3991
Joined: Fri Jul 24, 2015 2:28 am
Location: Las Vegas, USA
Thanked: 19 times
Followed by:37 members

Timer

00:00

Your Answer

A

B

C

D

E

Global Stats

[GMAT math practice question]

A total of 45 male and female students take a math test. The average score for the male students is 65 and the average score for the female students is 70. Also, the combined average score for the male and female students is 67. How many male students took the test?

A. 27
B. 31
C. 33
D. 35
E. 37
Source: — Problem Solving |

User avatar
Elite Legendary Member
Posts: 3991
Joined: Fri Jul 24, 2015 2:28 am
Location: Las Vegas, USA
Thanked: 19 times
Followed by:37 members

by Max@Math Revolution » Sun Aug 04, 2019 5:36 pm
=>

We can set up a 2x2 matrix using the data from the question as follows.
Image

The combined average is the total score divided by the total number of students. This value is
(65m + 70(45-m)) / 45 = 67.
Solving for m yields
65m + 3150 - 70m = 3015
-5m = -135
m = 27.

Therefore, the answer is A.
Answer: A