Q3 of 37 Page 195

50 villagers had taken 18 days to dig a pond. Let us calculate by using theory of variation how many extra persons will be required to dig the pond is 15 days.

Given: number of villagers (x) = 50

Number of days to dig a pond (y) = 18


Let New number of villagers (x1) = (x1)


New Number of days to dig = 15


As per given condition if the number of days reduced then number of villagers will increases than the previously given. Hence, it is the question of indirect proportion.


i.e. xy = x1y1


or 50 ×18 = 15 × x1



⇒ x1 = 60 days


Hence, 15 villagers will need 60 days.


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