<PRE><B>Question 824192</B>
For 6 tractors, their rate of ploughing the tract is
{{{ 120/4 = 30 }}} hectares/day
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1/6 as many tractors will plough the tract at
1/6 times that rate, so
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1 tractor will plow 1 tract in at a rate of {{{ 30/6 = 5 }}}
hectares/day
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4 tractors will plough at 4 times that rate, so
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4 tractors will plow 1 tract in at a rate of {{{ 4*5 = 20 }}}
hectares/day
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If the 4 tractors plough for 5 days, they will plough
{{{ 20*5 = 100 }}} hectares
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Hope I got it
 
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