A and B can finish a piece of work in 16 days and 12 days respectively .A started the work and worked at it for two days .he was then joined by B .find the total time taken to finish the work.
Answers
Answer:
A finishes the work in 16 days. A finishes 1/16 of the work in one day. in 1 day B finishes 1/12 of the work. A and B together can complete the remaining work= (7/8) / (7/48)= 7*48/8*7 = 6 days.
Solution :-
A and B can finish a piece of work in 16 days and 12 days
Therefore,
The work done by A and B in one day is 1/16 and 1/12
Now,
A is working alone and completed his work in 2 days = 2 * 1/16 = 1/8
Therefore,
Work left = 1 - 1/8 = 7/8
Now,
Work done by both A and B together in one day = 1/16 + 1/12 = 7/48
Therefore, they work upto 48/7 days
But, A and B completed 7/8th work
So ,
Time taken by A and B to complete 7/8th work
= 7/8 * 48/7 = 6 days
The total time taken to finish the work
= 6 + 2 = 8 days
[ We have added 2 because for two days A worked alone ]