Two persons P and Q working together can do a piece of work in 18 days. Q alone can do it in 36 days. Q started the work, and after working for 6 days he left the work. P then took up the remaining work. How many days will P take to complete the remaining work?
Show answer & explanation
Correct answer: B
Explanation
The correct answer is Option 2 i.e. 30.
Two persons P and Q working together can do a piece of work in 18 days. Q alone can do it in 36 days
L.C.M(18 and 36) = 36
The efficiency of P and Q = 36/18 = 2 unit
The efficiency of Q = 36/36 = 1 unit
So, the efficiency of P = 2 - 1 = 1 unit
Q work for only 6 days = 6 units
Remaining = 36 - 6 = 30 units
P will take = 30/1 = 30 days to complete the remaining work