In a class, there are 29 boys and 21 girls. The average score of boys in Maths is 89, whereas the average score of girls in maths is 91. What is the average of the whole class in maths?

89.84

Sum of score of boys in maths = 29 × 89 = 2581

Sum of scores of girls in maths  = 21 × 91 = 1911

Overall Average = \(\frac{2581 + 1911 }{29 + 21 }\) 

= \(\frac{4492}{50}\)  = 89.84