Question

the average age of 8 man is decreased by 2 years when two of them whose ages are 22 and 28 are replaced by two boys what is the average age of the two boys

Answer 1

x1+x2+x3+x4+x5+x6+22+28/8 = m
x1+x2+x3+x4+x5+x6 = 8m - 50

let t be average age of two boys who has been replaced:
x1+x2+x3+x4+x5+x6 + t/8 = m-2
8m - 50 +t/8 = m-2
8m- 50+t = 8m -16
t= 50-16
t = 34

therefore the average age of two boys is 34 yrs.