Question

Working together, a and b can do a job in 6 days. b and c can do the same job in 10 days, while c and a can do it in 7.5 days. how long will it take if all a, b and c work together to complete the job?

Answer 1

hope you satisfied,,,, good luck

Answer 2

Answer:

5 days

Step-by-step explanation:

A and B can do a job in 6 days. They complete 1/6th of the job in a day.  

i.e.

1 /A + 1 /B = 1 /6  ------- -- (1)

Similarly, B and C will complete 1 /10 th of the job in a day.  

i.e  

1 /B + 1 /C = 1 /10  ---------- (2)

And C and A will complete  1 /7.5  or  2 /15 th of the job in a day  

i.e  

1 /C + 1 /A = 2 /15  ------------ (3).

Adding (1), (2) and (3) we get:  

1/A+1/B+1/C= 1/5

i.e working together, A, B and C complete 1 /5 th of the job in a day.  

Therefore, they will complete the job in 5 days.