Select the correct answerP and Q together can do a job in 6 days. Q and R can finish the same job in 60/7 days. P started the work and worked for 3 days. Q and R continued for 6 days. Then the difference of days in which R and P can complete the job is?Options1581210

To solve this problem, we need to first find out the work done by P, Q, and R in one day.

1. P and Q together can do a job in 6 days. So, their combined work rate is 1/6 of the job per day.

2. Q and R together can do the same job in 60/7 days. So, their combined work rate is 7/60 of the job per day.

3. P started the work and worked for 3 days. So, P alone did 3*(1/6) = 1/2 of the job.

4. Q and R continued for 6 days. So, they together did 6*(7/60) = 7/10 of the job.

5. The total work done by P, Q, and R is 1/2 + 7/10 = 12/10 = 1.2 of the job. Since the total work cannot be more than 1, there must be an overlap in the work done by P and (Q, R). This overlap is the work done by Q, which is 1.2 - 1 = 0.2 of the job.

6. Since Q's work rate when working with P is (1/6) and when working with R is (7/60), we can set up the equation (1/6)x + (7/60)(6-x) = 0.2 to solve for x, which is the number of days Q worked with P. Solving this equation gives x = 2 days.

7. Therefore, Q worked with R for 6 - 2 = 4 days. Since Q and R together can do the job in 60/7 days, R alone can do the job in (60/7) / (1 - 1/6) = 10 days.

8. P alone can do the job in 6 / (1 - 1/10) = 15 days.

9. The difference in days in which R and P can complete the job is 15 - 10 = 5 days.

So, the correct answer is not in the options given. The difference should be 5 days.