DIRECTIONS for the question:Solve the following question and mark the best possible option.
A can do a piece of work in 15 days. He worked for 10 days. After this B did the remaining work in 10 days. How many days A and B will together take to finish the whole work?
A)
10 days
B)
20 days
C)
8 days
D)
None of these
A
Let the total work = 30 units
A's rate of doing work = 30/15 = 2 units/day
Work done by A in 10 days = 20 units
Remaining work = 30 - 20 = 10 units
Time taken by B to complete remaining work = 10 days
B's rate of doing work = 10/10 = 1 unit/day
Time taken by A and B together = 30/(2 + 1) = 10 days
