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Question
Twelve men and 5 women can complete a work in 2 days whereas 4 men and 3 women can complete the same work in 5 days. In how many days can 8 men complete the work?
Options
3
4
5
6
Solution
4
Explanation:
Let one man and one woman can complete the same work in x and y days respectively.
Then,
`12/"x"+5/"y"=1/2` ...........(i)
and `4/"x"+3/"y"=1/5` .............(ii)
From (i) and (ii), we have
`4/"y"=1/10`
⇒ y = 40 days.
then, `12/"x"+5/420=1/2`,
`"x"=(12xx8)/3=32` days.
∴ 8 men complete whole work in `32/8` = 4 days.
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