Ramu and Mohan can separately complete a work in 10 hours and 16 hours, respectively. After working for 2 hours together, Mohan leaves the work. In how many hours will Ramu finish the remaining work?
Show answer & explanation
Correct answer: B
Explanation
The coorrect answer is option 2 i.e. 6(3/4)
Ramu can complete the work in 10 hours.
Mohan can complete the work in 16 hours.
Work = Time × Efficiency
Total work = LCM(10, 16) = 80 units
Efficiency of Ramu = 80/10 = 8
Efficiency of Mohan = 80/16 = 5
When they work together, their combined efficiency = 8 + 5 = 13
They work together for 2 hours, so the amount of work they complete = 2 × 13 = 26 units
Remaining work = 80 - 26 = 54 units
Days taken by Ramu complete the remaining work = 54/8 = 27/4 = 6 3/4 hours