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?

Correct option is C

Given:
Boys = 20, Avg = 75
Girls = 30, Avg = 85
Formula Used:
​$$\text{Overall Average} = \frac{\text{Total Score}}{\text{Total Students}}$$​​
Solution:
Total score of boys = 20 × 75 = 1500
Total score of girls = 30 × 85 = 2550
Total score = 4050
Total students = 50
Overall average = $$\frac{4050}{ 50}$$​ = 81