Question 781076
 Samantha ran on a fitness track for 20 mins. She walked for 10 mins. Her running rate was 250ft per minute faster than her walking rate. If she ran and walked a total of 15,500ft, how fast did she run?

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Equations:
Distance Equation::: r + w = 15,500 ft
Rate Equation::::::: r/(1/5) =  w/(1/6) + 250 
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Modify for elimination:
6r + 6w = 6*15,500
6r - 5w = 30*250
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Subtract and solve for "w":
11w = 85,500
walking distance = 7772.73 ft
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running dstance = 7727.27 ft
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Cheers,
Stan H.
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