The average score in the Mathematics exam of a class of 60 students is 52. A group of 8 boys with an average score of 40 left the class and another group of 10 boys with an average score of 43 joined the class. What is the new average score of the class? (correct to one decimal place)
Show answer & explanation
Correct answer: C
Explanation
The correct answer is option 3 i.e 52.1.
Original total score = 60 students × 52 = 3120
Total score of 8 boys who left = 8 × 40 = 320
New total after they leave = 3120 − 320 = 2800
Total score of 10 boys who joined = 10 × 43 = 430
New total after they join = 2800 + 430 = 3230
New total number of students = 60 − 8 + 10 =62
New average = 3230 ÷ 62 = 52.1