Q:

# Mrs Dang drove her daughter to school at the average speed of 45 miles per hour. She returned home by the same route at the average speed of 30 miles per hour. If the trip took one half hour, how long did it take to get to school? How far is the school from their home?

Accepted Solution

A:
Answer: Time it took her to get to the school is 0.6 hoursThe distance of the school from their home is 27 milesStep-by-step explanation:Mrs Dang drove her daughter to school at the average speed of 45 miles per hour.Let x miles = distance from the school to their home. Distance = speed Γ timeTime = distance / speedTime used in going to school will bex/45She returned home by the same route. This means that distance back home is also x miles.She returned at an average speed of 30 miles per hour.Time used in returning home from school will be x/30x/45If the trip took one half hour, then the time spent in going to school and the time spent in returning is 1 1/2 hours = 1.5 hours. Thereforex/30 + x/45 = 1.5(15x + 10x) /450 = 1.515x + 10x = 450 Γ 1.5 = 67525x = 675x = 675/25 = 27Time it took her to get to the school will be x/45 = 27/45 = 0.6 hours