Question

Michelle rode her bicycle from her house to school at an average speed of 8 miles per hour. Later that day, she rode from school back home along the same route at an average speed of 12 miles per hour. If the round trip took one hour, how many miles long is the round trip?

Answer 1

9514 1404 393

Answer:

9.6 miles

Explanation:

Let x represent the round trip distance. Then Michelle's time was ...

t = distance/speed

1 = (x/2)/8 +(x/2)/12 = x(1/16 +1/24) = x(3/48 +2/48) = x(5/48)

48/5 = x = 9.6

The round trip is 9.6 miles.