If A can complete a task in 24 hours and B can complete the same task in 36 hours, how long will it

A. 14.4 hours

B. 15 hours

C. 16 hours

D. 12 hours

E. None of the above

Answer: A. 14.4 hours

A's rate is 1/24 and B's is 1/36. Together, they work at a rate of 1/24 + 1/36 = 5/72. Therefore, they will complete the work in 72/5 = 14.4 hours.

Posted in: Time & Work - Aptitude - Mathematics