You can ride a bicycle 15 mph Your sister rides 12 mph You g

You can ride a bicycle 15 mph. Your sister rides 12 mph. You give her a one hour head start. In how many hours will you catch up if neither of you stops.

Solution

Your DATA:
rate = 15 mph ; time = x hrs ; distance = rt = 15x miles
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Sister\'s DATA:
rate = 12 mph ; time = x+1 hrs ; distance = 12(x+1) miles
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Equation:
distance = distance
15x = 12(x+1)
3x = 12
x = 4 hrs
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