A and B can do a work in 12 days and 16 days, respectively. If they work together for 6 days, then the fraction of the work left is _________.
Show answer & explanation
Correct answer: C
Explanation
The correct answer is option 3 i.e. .
Time required for A to do the work = 12 days
So, A does 1/12 of the work in 1 day.
Time required for B to do the work = 16 days
So, B does 1/16 of the work in 1 day.
Work done by A and B together in 1 day = (1/12) + (1/16) = 7/48 of the work
Work done by A and B together in 6 days = (7/48) × 6 = 7/8 of the work
Remaining work = 1 - (7/8) = 1/8
Therefore, the fraction of the work left is 1/8.