Question

a can do a piece of work in 80 days he worked it for 10 days and then B alone finish the work in 42 days The two togethers could complete the work in how many days ​

Answer 1

do part of park in 1 day=1/80

Work done by ajay in 10 days=10/80

=1/8

Remaining work=1-1/8

=7/8

B complete in 42 days=7/8part of work

B can complete in1day=1/48part of work

So B alone can complete it in 48 days

Work done by both in 1 day

=1/80+1/48

=(3+5)/240

=1/30

So they can finish the work together in 30days

Answer 2

Step-by-step explanation:

Total Work = 80 units

A --> 80 days = 1 unit / day

In 10 days A has completed 10 units

Remaining work = 70 units

B finishes it in 42 days

Rate of work if B = 70 / 42 = 5/3 unit / day

A + B = 1 + 5/3 = 8/3

Time taken if both A and B will work together = 80/8/3

= 30 days

Hope it will help you .