Question

A and b working separately complete a piece of work in 20 days and 30 days respectively.they worked together for some time then bleft the work if a completed the rest of the work in 10 days then b worked for

Answer 1

Heya
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Here is the answer

Work done by A in 10 days = 10/20 = ½

Days required by (A+B) together to complete ½ work = ½ /(1/20 + 1/30)= 6 days


hope it helps to you.

Answer 2

since A's 1 day work =1/20
work done by A alone in 10 days =1/20*10=1/2
work done by A and B together =1-1/2=1/2
(A+B)'s 1 day work =1/20+1/30=1/12
No of days A and B worked together =1/2/1/12=12/2=6

Hence B left work after 6 days