The number of students in a class is 75, out of which 
are boys and the rest are girls. The average score in mathematics of the boys is 
more than that of the girls. If the average score of all the students is 66, then the average score of the girls is ?
Show answer & explanation
Correct answer: C
Explanation
The correct answer is option 3 ie 54.
Boys : Girls
1 : 2
5x : 3x
(5x+6x) / 3 = 66
11x = 198
x = 18
3x = 18 × 3 = 54