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a boy and his sister ran some laps the boy ran 2.5 times as many left as his sister together they run seven laps how many laps did each one

User NoSkill
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1 Answer

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Let the laps run by the sister be x

The laps run by the boy is 2.5 times the laps by the sister. Thus the laps run by the boy is


2.5x

The total laps by the boy and the girl is 7. Therefore,


\begin{gathered} x+2.5x=7 \\ 3.5x=7 \\ x=(7)/(3.5)=2 \\ \text{The laps by sister is 2.} \\ 2.5x=2.5\ast2=5 \\ \text{Thus, the laps by boy is 5} \end{gathered}

User Comzyh
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