A can finish of a task in 12 days and B can finish of the same task in 30 days. They work together for 10 days. C alone completes the remaining task in 16 days. B and C together will complete of the same task in:
Show answer & explanation
Correct answer: A
Explanation
The correct answer is option 1 i.e.16 days.
Time taken by A to complete the whole work = 12 × = 6 × 5 = 30 days
Time taken by B to complete the whole work = 30 × = 15 × 3 = 45 days
LCM(30, 45) = 90
The efficiency of A = 90/30 = 3 units
The efficiency of B = 90/45 = 2 units
Work done by A and B in 10 days = 10 × 5 = 50 units
Remaining work = 90 - 50 = 40 units
The efficiency of C = = units
⇒ × 90 = 4 × 18 = 72 units
Time taken by B and C = = = 16 days