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Starting at home, Emily traveled uphill to the hardware store for 60 minutes at just 6 mph. She then traveled back home along the same path downhill at a speed of 12 mph. What is her average speed for the entire trip from home to the hardware store and back? (I need the rate version for this. 24 and 6 are not correct)

1 Answer

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The distance traveled was 6 miles (6 mph times 1 hour).

The total distance traveled was 12 miles.

The downhill journey lasted (6 mi) / (12 mph), or 1/2 hr.

Thus, the average speed was

12 miles 12 mi
------------- = ------------ = 8 mph
(1 1/2 hr) (3/2) hr
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