Question

A can do a piece of work in 80 days and B in 100 days. They worked together for 20 days
then B goes away. In how many days will A finish the remaining work

Answer 1

Hello mate here is your answer

It's given that

A can do a piece of work in = 80 days

A's 1 day work is = 1/80

B can do a piece of work in = 100 days

B's 1 day work is 1/100

If A and B work together they take time :-

( A+B )'s 1 day work is = (1/80) + (1/100)

= { ( 50+4 ) / 400 }

= 54/ 400

A and B work together for 20 days

Now,

(A+B ) 's 1 day work = 54/400

(A+B) 's 20 day work is = 20×54/400

= 54/20

Remaining work is = [ 1-54/200 ]

= [( 200 - 54) /200 ]

= 146/200

Now, after it B left the work

Alone A's work in 1 day is = 1/80

and the remaining work is 146/200

Now,

How many days taken by A to finish the work =

(146/200)×80

= 146/20 × 8

146/5 ×2

292/5

58 ⅖ days Answer

Hopefully It will help you

I don't know if it is correct or not