A student walks and jogs to college each day. The student averages 5 mph walking and9mph jogging. The distance is 8. She makes the trip in one hour. How far does the student jog?

Let x = the distance jogged

Then (8-x) = distance walked

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Write a time equation: Time = dist/speed

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Jog time + walk time = 1 hr

x%2F9 + %28%288-x%29%29%2F5%29 = 1

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Multiply thru by 45 to get rid of the denominators, resulting in:

5x + 9 (8-x) = 45

:

5x + 72 - 9x = 45

-4x = 45 - 72

-4x = - 27

x = - 27/-4

x = + 6.75 km jogged

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Check: 8 - 6.75 = 1.25 km walked

6.75/9 + 1.25/5 =

.75 +.25 = 1