Question

A and B together can do a piece of work in 20 day , B and c together can do it in 15 day ,c and A together can do it in 12 days 1. how long will they take to finish the work, working all together? ​

Answer 1

Answer:

You will be 10 days

Step-by-step explanation:

Put value of A in equation 3 we get

-1/30 + c = 1/12

C= 1/12 +1/30

C= 7/60

Add A, B, C

-1/30+ 1/60+7/60

= -1/30 + 8/60

= -2/60 + 8/60. taking LCM

= 6/60

= 1/10

1 work in 10 days

Answer 2

Step-by-step explanation:

Given :-

• A and B together can do a piece of work in 15 days, B and C together can do it in 12 days, A and C can do it in 20 days.

To Find :-

• How long will they take to finish the work together?

Solution :-

At first

We have

A + B = 15

B + C = 12

A + C = 20

Work done in 1 day

A + B = 1/15

B + C = 1/12

A + C = 1/20

When they do work together

(A + B) + (B + C) + (A + C) = (1/15) + (1/12) + (1/20)

A + B + B + C + A + C = 1/15 + 1/12 + 1/20

2A + 2B + 2C = 1(4) + 1(5) + 1(3)/60

2A + 2B + 2C = 4 + 5 + 3/60

2(A + B + C) = 12/60

2(A + B + C) = ⅕

2(A + B + C)/2 = ⅕/2

A + B + C = ⅕ × ½

A + B + C = 1/10.

Work done by A + B + C in one day = 1/10

Total days taken = 10 days