Question

rajan can do a piece of work in 24 days while amit can do it in 30 days in how many days can they complete it .

Answer 1

Rajan can in 24 days finish the full work i.e 100% or 1 of it.
∴ Rajan can in 1 day finish 1/24th of the work.

Amit can in 30 days finish the full work i.e 100% or 1 of it.
∴ Amit can in 1 day finish 1/30th of the work.

Therefore amount of work both of them can do in 1 day
= 1/24+1/30
= 24+30/720
= 54/720
= 3/40

Therefore time taken by them = 1/(3/40) = 40/3 = 13 1/3 days

Answer 2

Answer:

Rajan can in 24 days finish the full work i.e 100% or 1 of it.

∴ Rajan can in 1 day finish 1/24th of the work.

Amit can in 30 days finish the full work i.e 100% or 1 of it.

∴ Amit can in 1 day finish 1/30th of the work.

Therefore amount of work both of them can do in 1 day

= 1/24+1/30

= 24+30/720

= 54/720

= 3/40

Therefore time taken by them = 1/(3/40) = 40/3 = 13 1/3 days