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Question
Shaheed can prepare one wooden chair in 3 days and Shaif can prepare the same chair in 4 days. If they work together, in how many days will they prepare:
(i) one chair?
(ii)14 chairs of the same kind?
Solution
Shaheed's 1 day's work = `1/3`
and Shaif's 1 day's work = `1/4`
Both one day's work `= 1/3 + 1/4 = (4 + 3)/12 = 7/12`
∴ Both can prepare the chair in =`12/7` days
`= 1 5/7` days
One chair is prepared in = `1 5/7` days
∴ 14 chairs will be prepared in = `12/7 xx 14 = 24` days.
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