Bhanu can do a work in 10 days. Ramesh takes 12 days to complete it. Rohit takes as long as Bhanu and Ramesh would work together. How long will it take Ramesh and Rohit to complete the work together?
Show answer & explanation
Correct answer: C
Explanation
The correct answer is Option 3 i.e. days.
Bhanu can do the work in 10 days, so his one-day work = 1/10 units
Ramesh can do the work in 12 days, so his one-day work = 1/12 units
Rohit takes as long as Bhanu and Ramesh working together, so their combined work rate is:
1/10 + 1/12 = (12 + 10)/120 = 22/120 = 11/60 units/day
Now, to find out how long it will take Ramesh and Rohit to complete the work together, we can add their work rates:
To complete the entire job, it will take them 1 divided by their combined work rate:
1/(4/15) = 15/4 = 3.75 = days