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Tom and Jerry can mow the Steeleford Estate in 3 hours when working together. Jerry can complete the mowing in x hours when working alone. Tom would take twice as long as Jerry to do this job. How long would it take each of them to mow the estate alone?

1 Answer

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Both Tom and Jerry can mow the estate in 3 hours

Jerry alone can mow the estate in x hours; Jerry's rate = 1/x mow/hour

Tom would mow the estate in 2x hours; Tom's rate = 1/2x mow/hour


\begin{gathered} (1)/(x)+(1)/(2x)=(2+1)/(2x)=(3)/(2x) \\ So,\text{ it follows that,} \\ (2x)/(3)=3 \\ \text{cross multiply to get,} \\ 2x=3*3 \\ 2x=9 \\ x=(9)/(2)=4.5\text{ hours} \end{gathered}

Jerry would take 4.5 hours to mow the estate, while

Tom would take 2x4.5 = 9 hours to mow the estate.

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