Q. 144.4( 11 Votes )

# An agricultural Co-operative Society of village of Pachla has purchased a tractor. Previously 2400 bighas of land were cultivated by 25 ploughs in 36 days. Now half of the land can be cultivated only by that-tractor in 30 days. Let us calculate by using the theory of variation, the number of ploughs work equally with one tractor.

Answer :

Given:

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

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

Acc. To given values,

For, D = 30, Bighas of land = 1200

So, 15 ploughs are needed for 1200 bighas of land in 30 days.

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