Q and R together are 3 times as efficient as P. P and R together are 2.5 times as efficient as Q. Q and R together can complete a work in 60 days. P alone can complete the same work in how many days?
Show answer & explanation
Correct answer: B
Explanation
Let the efficiencies of P, Q, and R be p, q, and r, respectively.
Given:
Q + R = 3P
P + R = 2.5Q
Q + R = 1/60
3P = 1/60
P = 1/180
Therefore, P alone will complete the work in 180 days.