• We assume here that the auto drives at 40 mph for 4 hours.
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• Then, it stops and then drives for 2 hours at 10 mph.
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• We need to find the total miles the auto drove.
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• To answer this question, we need to know that we have a constant rate at each part of the driving of the auto: in the first part, it drove at a constant speed of 40 mph. In the second part, it drove at a constant speed of 10 mph.
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• We can say that the total distance for the first part is:
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• d1 = 40 miles/hour * 4 hours ---> ,d1 = 160 miles.
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• In the second part:
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• d2 = 10 miles/hour * 2 hours ---> ,d2 = 20 miles.
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• Then, the total miles it went was:
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• ,d1 + d2 = 160 miles + 20 miles = 180 miles.
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• The auto drove for 180 miles.
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