p' and 'q' can do a job in 15 days and 10 days respectively. they began the work together but 'p' leaves after some days and 'q' finishes the remaining job in 5 days. after how many days did 'p' leave?
Answers
Given, P and Q can complete a work in 15 days and 10 days respectively.
= The amount of work done by them together in 1 day = 1/15 + 1/10
= (2+3)/30 = 5/30 = 1/6
Given, they worked together for 2 days.
= The amount of work done by them together = 2*(1/6) = 1/3
The amount of work to be completed by P alone = 1 - 1/3 = 2/3
The number of days taken by P alone to complete the remaining work = (2/3)/(1/15) = 30/3 = 10
= The whole work was completed in (2+10) i.e., 12 days.
Answer:
3 days
Step-by-step explanation:
Given
p does a job in 15 days. So 1 day work is 1/15
q does job in 10 days. So 1 day work is 1/10.
Work done by p and q in 1 day = 1/15 + 1/10 = 1/6 th of work.
Q completes remaining job alone in 5 days. Hence amount of work done by Q in 5 days is 5 * 1/10 = 1/2.
So P and Q did 1/2 work (1 - 1/2) together before P left after x days.
No of days required by P & Q to complete 1/2 work = 6 * 1/2 = 3 days.