57.
|
A and B can complete a work in 15 days and 10 days respectively. They started doing the work together but after 2 days B had to leave and A alone completed the remaining work. The whole work was completed in :
|
|
|
8 days
|
|
10 days
|
|
|
12 days
|
|
15 days
|
|
Answer: Option C
Explanation:
(A + B)'s 1 day's work =
|
|
1
|
+
|
1
|
|
=
|
1
|
.
|
15
|
10
|
6
|
Work done by A and B in 2 days =
|
|
1
|
x 2
|
|
=
|
1
|
.
|
6
|
3
|
Remaining work =
|
|
1 -
|
1
|
|
=
|
2
|
.
|
3
|
3
|
Now,
|
1
|
work is done by A in 1 day.
|
15
|
|
2
|
work will be done by a in
|
|
15 x
|
2
|
|
= 10 days.
|
3
|
3
|
Hence, the total time taken = (10 + 2) = 12 days.
