Question

The average age of 5 boys is 12. The average age of 3 others is 16. The average age of all the 8 boys is a) 10.5 yrs b) 11.5 yrs c) 12.5 yrs d) 13.5 yrs

Answer 1

avg age of 5 boys = 12
total age of 5 is 12×5=60
avg of 3 boys = 16
total age of 3 = 3×16=48
total age of 8 boys = 60+48=108
avg of 8 boys = 108/8=13.5