Question

A is able to complete `1/3` of a certain work in 10 hrs and B is able to complete `2/5` of the same work in 12 hrs. Find:

(i) how much work can A do in 1 hour ?
(ii) how much work can B do in 1 hour ?
(iii) in how much time will the work be completed, if both work together.

Answer 1

A can do `1/3` of work in = 10 hours

∴ A can do full work in `= (10 xx 3)/1 = 30` hours

B can do `2/5` of the work in = 12 hours

∴ B can do the whole work in =`(12 xx 5)/2` = 30 hours

(i) Now A's 1 hour's work = `1/30`

(ii) B's 1 hours work = `1/30`

(iii) Both's 1 hour's work

`=1/30 + 1/30 = 2/30 = 1/15`

∴ Both can finish the work in 15 hours