A can do a work in 10 days, B in 15 days, and C in 30 days. If all three work together for 3 days and then A leaves, in how many more days will the remaining work be finished?
Show answer & explanation
Correct answer: B
Explanation
Given:
A's time = 10 days
B's time = 15 days
C's time = 30 days
All three work together = 3 days
A's rate = 1/10
B's rate = 1/15
C's rate = 1/30
Rates of all three = 1/10 + 1/15 + 1/30 = 1/5
Work done in 3 days = 3 × 1/5 = 3/5
Remaining work = 1 − 3/5 = 2/5
Rates of B and C = 1/15 + 1/30 = 1/10
Time = (2/5) ÷ (1/10) = 4 days