Question

A and B together complete a work in 15 days. A alone can do it in 20 days. In how many days B alone can do it?

Answer 1

$\underline{\underline{\Huge\mathfrak{Answer ;}}}$

=> A and B → 15 days

=> A → 20days

• So, let's take LCM of 15 and 20. That's 60.

{ Remember: This 60 unit is the total work to be done. }

• So, A and B do (60/15) = 4 unit work/day …(1)

• And, A does (60/20) = 3 unit work/day …(2)

=> (1)-(2) gives

=> B does (4–3)= 1 unit/day

• So, Total days req. = (Total work)/unit per day

=> i.e, B can do it in (60/1)=60 days.

_______________________

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@dmohit432

Answer 2

hey

here is answer

> A and B do work in 15 days

=> A do its work in 20days

LCM of 15 and 20.

=60



A and B do (60/15) = 4 unit work/day …(1)

And,

A does (60/20) = 3 unit work/day …(2)

=>from equation (1)-(2)

=> B does (4–3)= 1 unit work /day

• So,


Total days = Total work/unit per day


hence answer=60days.

hope it helps


thanks