5 years ago, the average age of P and Q was 15 years. Average age of P, Q and R today Is 20 years. How old will R be after 10 years?

Options

A. 35 yr
B. 40 yr
C. 30 yr
D. 50 yr

Answer

C

Explanation

According to the question,
`((P + Q)/(2)) - 5 = 15 implies (P + Q)/(2) = 20`
`implies P + Q = 40 " " ....(i)`
and `(P + Q + R)/(3) = 20`
`P + Q + R = 60`
From Eqs. (i) and (ii),
`R = 20 yr `
`therefore` Age of R after 10 yr from now = `20 + 10`
`= 30 yr `