In a class of 50 students there are 22 girls who scored an average of 35 marks in the test. What is the average marks of the boys if the class average is 42 marks ?
Show answer & explanation
Correct answer: C
Explanation
The correct answer is option 3 ie 47.5.
Sum of scores of all students = 50 × 42 = 2100
Sum of scores of 22 girls = 35 × 22 = 770
Sum of scores of boys = 2100 - 770 = 1330
Average score of boys = 1330/28 = 47.5