<PRE><B>Question 857421</B>
Each of the four tractors plant at the same rate.  You are given THREE of these identical tractors plant 270 acres in 3 hours.  Again since these tractors are identical and work at the same rate each, the {{{270/3}}} acres/hour rate is three times bigger than for just a single tractor.


T is the rate of 1 tractor.
You have {{{highlight_green(T+T+T=270/3)}}}  in units of acres per hour.
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{{{3T=270/3}}}
{{{T=270/(3*3)}}}
{{{T=(3*3*3*10)/(3*3)}}}
{{{highlight_green(T=30)}}} acres per hour, for ONE tractor.
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Now, your question is like 4T for all four of these identical tractors; and you want to know how many acres are planted in 5 hours.
{{{highlight((4T)*5=(4*30)*5*(acres/hour)*hour=120)}}} acres</PRE>