In a class, the average score of boys is 75 with 20 boys and the average score of girls is 85 with 30 girls. What is the overall average score of the class?
Show answer & explanation
Correct answer: C
Explanation
The correct answer is Option 3 i.e. 81.
Overall average = (Total boys score + Total girls score) ÷ Total students
= (75 × 20 + 85 × 30) ÷ (20 + 30)
= (1500 + 2550) ÷ 50 = 4050 ÷ 50 = 81