Rohan can alone finish a work in 12 days and Hari can alone in 16 days. They both work for 3 days and then Rohan left. After that only Hari works and finishes the work. The total work will be completed in:
Show answer & explanation
Correct answer: A
Explanation
The correct answer is option 1 i.e. 12 days.
Time required for Rohan to finish the work = 12 days
Rohan's one-day work = 1/12
Time required for Hari to finish the work = 16 days
Hari's one-day work = 1/16
Rohan and Hari's one-day work together = (1/12) + (1/16) = 7/48
Work done in 3 days = 3 × (7/48) = 7/16
Remaining work: 1 - (7/16) = 9/16
Time required by Hari to complete the remaining work = (9/16)/(1/16) = 9 days
Total time required = Time worked together + Time Hari worked alone = 3 + 9 = 12 days
Therefore, the total work will be completed in 12 days.