15 boys and a certain number of girls appeared for a test. The average score of the boys was 26; the average score of the girls was 36, while the combined average score was 30. How many girls appeared for the test?

10 8 12 9

10

Let number of girls = A ATQ , 15 × 26 + A × 36 = ( 15 + A ) × 30 390 + 36A = 450 + 30A 6A = 60 A = 10 So , Number of girls who appeared in test are 10