36. The average age of P, Q, R and S is 30 years. How old is R?
I. The sum of ages of P and R is 60 years.
II. S is 10 years younger than R.
A. I alone sufficient while II alone not sufficient to answer
B. II alone sufficient while I alone not sufficient to answer
C. Either I or II alone sufficient to answer
D. Both I and II are not sufficient to answer
E. Both I and II are necessary to answer
Answer: Option D
Explanation:
P + Q + R + S = (30 x 4) P + Q + R + S = 120 .... (i)
I. P + R = 60 .... (ii)
II. S = (R - 10) .... (iii)
From (i), (ii) and (iii), we cannot find R.
Correct answer is (D)
