In a dairy farm, 40 cows eat 40 bags of husk in 40 days. In how many days one cow will eat one bag of husk?	Choices.
A) 32 B) 36 C) 38 D) 40 E) 50
Assume that in x days, one cow will eat one bag of husk.   More cows, less days (Indirect proportion)   More bags, more days (direct proportion)   Hence we can write as   (cows)40:1   (bags)1:40   x:40   =40×1×40=1×40×x   =x=40   ANSWER : 40
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In a dairy farm, 40 cows eat 40 bags of husk in 40 days. In how many days one cow will eat one bag of husk?