Starting at home, Jessica traveled uphill to the toy store for 12 minutes at just 10 mph. She then traveled back home along the same path downhill at a speed of 30 mph. What is her average speed for the entire trip from home to the toy store and back?

Answer:15 miles per hourStep-by-step explanation:Average Speed is:Average Speed = Total Distance/Total TimeGoing uphill, she took 12 minuets, that is hours is 12/60 = 0.2 hoursWe know D = RT, Distance = Rate(speed) * TimeThus,D = 10mph * 0.2 hr = 2 milesSo, total distance (uphill and downhill) = 2 + 2 = 4 milesDownhill the time she took isD = RT2miles = 30mph * TT = 2/30 = 1/15 hours = 1/15 * 60 = 4 minutesHence total time is 12 + 4 = 16 minutesNote: 16 minutes = 16/60 = 4/15 hoursNowAverage Speed = Total Distance/Total TimeAverage Speed = 4 miles/ 4/15 hours = 15 mph