A, B, and C together can do a piece of work in 6 days. A and B together can do the same work in 12 days. B alone can do the same work in 18 days. In how many days can A and C together do the same work?
Show answer & explanation
Correct answer: A
Explanation
The correct answer is option 1 i.e. 9 days.
Calculations:
Let the total work be 18 units (LCM of 6, 12, and 18)
Efficiency of A, B, and C = 18/6 = 3 units
Efficiency of A and B = 18/12 = 1.5 units
Efficiency of B = 18/18 = 1 units
Efficiency of A = 1.5 - 1 = 0.5 unit
Efficiency of C = 3 - 1.5 = 1.5 unit
Required time = 18/2 = 9 days