P, Q, R, and S are all 30 years old on average. What is R's age? I. P and R have a combined age of 60 years. II. S is ten years R's junior.
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
Answer:D
P, Q, R, and S are all 30 years old on average. What is R's age? I. P and R have a combined age of 60 years. II. S is ten years R's junior.
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
Explanation: S = P + Q + R + S = P + Q + R + S = P + Q + R (30 x 4) 120 = P + Q + R + S... (i),P + R = 60 I. P + R = 60 I. P + R = 60 I. P + R = (ii),II. (R - 10) = S... (iii),We can't find R in I (ii), or (iii).