Answer with Explanation:
(A + B)'s 1 day's work = ( 1/15 + 1/10) = 1/6.
Work done by A and B in 2 days = (1/6 x 2) = 1/3.
Remaining work = (1 - 1/3) = 2/3 .
Now, 1/15 work is done by A in 1 day.
Therefore 2/3 work will be done by a in (15 x 2/3) = 10 Days.
Hence, the total time taken = (10 + 2) = 12 Days.
(A + B)'s 1 day's work = ( 1/15 + 1/10) = 1/6.
Work done by A and B in 2 days = (1/6 x 2) = 1/3.
Remaining work = (1 - 1/3) = 2/3 .
Now, 1/15 work is done by A in 1 day.
Therefore 2/3 work will be done by a in (15 x 2/3) = 10 Days.
Hence, the total time taken = (10 + 2) = 12 Days.