36 men can complete a work in 36 days. They started working together. But 6 men kept on leaving the job every 7th day. In how many days will the work be completed?
Show answer & explanation
Correct answer: C
Explanation
Work = 36 × 36 = 1296 man-days
Work done in first 42 days:
7 × (36 + 30 + 24 + 18 + 12 + 6)
= 7 × 126
= 882 man-days
Remaining work:
1296 − 882 = 414 man-days
Remaining 6 men complete it in:
414 ÷ 6 = 69 days
Total time = 42 + 69 = 111 days
Answer: 111 days (Option 3)