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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.
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Solution
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
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