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A cyclist rode the first 14-mile portion of his workout at a constant speed. For the 10-mile cooldown portion, of his workout, he reduced his speed by 2 miles per hour. Each portion of the workout took the same time. Find the cyclist's speed during the first portion and find his speed during the cooldown portion.

User GLee
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1 Answer

6 votes

Step-by-step explanation

To solve the question, we will have to make use of the fact that


time=(distance)/(speed)

So, we can make the initial speed = v

Thus, we will have the equation:

For the first part


time=(14)/(v)

For the second portion, since he reduced the speed by 2miles/hour, the time will be


time=(10)/(v-2)

Also, we are told the time for the first and second part of the journey are equal, therefore


(14)/(v)=(10)/(v-2)

If we solve for v


\begin{gathered} 14(v-2)=10v \\ 14v-28=10v \\ 14v-10v=28 \\ 4v=28 \\ \\ v=(28)/(4) \\ \\ v=7 \end{gathered}

Therefore, the cyclist's speed during the first portion is 7 miles per hour

Also

His speed during the cooldown portion will be (7-2)miles per hour = 5 miles per hour

User Gianluca Micchi
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