Question

A aur B kisi kam ko 30 din me karte h, unhone 20 dino tak kam kiya uske bad B ne kam chhod diya, bacha hua kam A ne akele kiya jisme 20 din ka samay lga, to bataye ki A akele us kam ko kitne dino me karega

Answer 1

If A takes 20 days to complete something that both A&B can finish in 10 days, then A will take 60 days to complete the work that both A&B working together can finish in 30 days

Answer 2

let total work is 1
A+B complete total work (1) in 30 days
then (A+B)'s 1 day work = 1/30
then (A+B)'s 20 days work = 20/30=2/3
now remaining work = 1-2/3 = 1/3
1/3 work is done by A in 20 days
then total work (1) will be done in 20×3 = 60 days.