The average marks of 30 students are 72. The top 5 students scored an average of 86 marks, while the last 5 students averaged 54. What is the average of the remaining 20 students?
Show answer & explanation
Correct answer: B
Explanation
Total marks of 30 students = 30 × 72 = 2160
Total marks of the top 5 students = 5 × 86 = 430
Total marks of the bottom 5 students = 5 × 54 = 270
Total marks of the remaining 20 students = 2160 − 430 − 270
= 1460
Average of the remaining 20 students = 1460/20 = 73