Question

the average of 12 boys is 10 years out of these the average of 11 boys is 9 years find the age of 12 boys​

Answer 1

Answer:

average of 12 boys=

average of 12 boys=total age of 12 boys/ total boys

average of 12 boys=total age of 12 boys/ total boysaccording to question ::--

average of 12 boys=total age of 12 boys/ total boysaccording to question ::--total age of 12 boys = 12 × 10 = 120

average of 12 boys=total age of 12 boys/ total boysaccording to question ::--total age of 12 boys = 12 × 10 = 120total age of 11 boys = 11 × 9 = 99

average of 12 boys=total age of 12 boys/ total boysaccording to question ::--total age of 12 boys = 12 × 10 = 120total age of 11 boys = 11 × 9 = 99we can write total age of 12 boys =

average of 12 boys=total age of 12 boys/ total boysaccording to question ::--total age of 12 boys = 12 × 10 = 120total age of 11 boys = 11 × 9 = 99we can write total age of 12 boys =(age of 11 boys + age of 12th boy)

average of 12 boys=total age of 12 boys/ total boysaccording to question ::--total age of 12 boys = 12 × 10 = 120total age of 11 boys = 11 × 9 = 99we can write total age of 12 boys =(age of 11 boys + age of 12th boy)120 = 99 + age of 12th boy

average of 12 boys=total age of 12 boys/ total boysaccording to question ::--total age of 12 boys = 12 × 10 = 120total age of 11 boys = 11 × 9 = 99we can write total age of 12 boys =(age of 11 boys + age of 12th boy)120 = 99 + age of 12th boyage of 12th boy = 21

Answer 2

12*10=120
11*9=99
120-99=21
So that the answer is 21