DIRECTIONS for the question:Solve the following question and mark the best possible option.
C and D can complete the job in 9 days. If C worked twice as efficiently as he actually did and D worked ½ as efficient as he actually did, the work would have been completed in 6 days. D alone can complete the work in :
A)
27 days
B)
23 days
C)
22 days
D)
28 days
A
Given, C + D = W/9
Also, 2C + D/2 = W/6
Multiplying 1st equation with 2 and subtracting,
2D - D/2 = 2W/9 - W/6 = W/18
=> D = W/27
Hence, D alone can complete the work in 27 days