Q8 of 37 Page 195

If 15 farmers can cultivate 18 bighas of land in 5 days, let us determine by using theory of variation the number of days required by 10 farmers to cultivate 12 bighas of land.

Given:

More will be the number of farmers, more bighas of land will be cultivated i.e. direct proportion.


More will be farmers, less number of days will be needed i.e. indirect proportion.





Acc. To given values,




For, F = 10, Bighas of land = 12




⇒ D = 5days


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