A is thrice as efficient as B. Together they can complete a work in 12 days. In how many days can B alone complete the work?
Show answer & explanation
Correct answer: A
Explanation
Efficiency of A : B = 3 : 1
Let the 1-day work efficiency of A and B be 3x and x, respectively.
Combined efficiency of both = 4x
Together, they complete the work in 12 days; therefore,
4x = 1/12
x = 1/48
Thus, B's 1-day work efficiency = 1/48
Therefore, B alone will complete the work in 48 days.