solved answer throughly with explanation
Answers
A and B can complete the work in 30 days.
A and B 's one day work would be 1/30.....................(1)
A and B work for 20 days .
Then B leaves the work.
During this course of time :
work done ==> 1 day's work × 20
==> 1/30 × 20 [ from (1) ]
==> 20 / 30
==> 2/3
Remaining part of the work = 1 - 2/3
==> ( 3 - 2)/3
==> 1/3
A finished in 20 days 1/3 th of the work.
Then the whole work he can do 1/3 × 3 th work in 20 × 3 days
==> the complete work in 60 days.
A alone can complete the work in 60 days .
Hope it helps
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