Question 124672
A girl walked from her home into town at the rate of 4 miles per hour. She returned by bus over the same route. The bus averaged 20 miles per hour, and the entire round trip took 1 hour and 40 minutes, including the 10 minute wait for the bus. How far did the girl walk?
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Let's subtract the 10 min wait; The travel time totals 1.5 hrs
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Let d = distance walked (and distance by bus)
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Write a time equation: Time = Distance/speed
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Walk time + Bus time = 1.5 hrs
{{{d/4}}} + {{{d/20}}} = 1.5
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Multiply equation by 20 to get rid of the denominators
5d + d = 20(1.5)
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6d = 30
d ={{{30/6}}}
d = 5 miles is the distance walked
:
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Check solution by finding the time
{{{5/4}}} + {{{5/20}}} =
   1.25 + .25 = 1.5