Question

The ratio of the number of boys and girls in a class is 2: 3 and the average score in mathematics of all the students in the class is 54. The average score of boys is 50% higher than the average score of girls. What is the average score of girls? (a) 50 (b) 42 (c) 45 (d) 40​

Answer 1

I think I should be 45

Answer 2

Explanation:

Let average score of girls be 2x

Average score of boys = 2x × 3/2 = 3x

Ratio of boys and girls = 2 : 3

Let number of boys be = 2 and number of girls = 3

According to the question

⇒ 2 × 3x + 3 × 2x = 54 × 5

⇒ 6x + 6x = 270

⇒ 12x = 270

⇒ x = 270/12

Average score of girls = 2 × 270/12 = 45