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Question
Three persons can build a small house in 8 days. To build the same house in 6 days, how many persons are required?
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Solution
Let the number of persons required to build the same house in 6 days be x.
The number of persons and the number of days required to build the house are in inverse variation. So, the product of number of persons and the number of days required to build the house is constant.
∴ x × 6 = 3 × 8
⇒ x = ` (3 xx 8) /6 = 24/6 = 4`
∴ x = 4
Thus, 4 persons are required to build the same house in 6 days.
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