Maya can run 18 miles in 3 hours, and she can bike 18 miles in 2 hours. When Maya biked for 3 hours and then ran for 1 hour and 30 minutes, what was her average speed?

Answer: 8

Step-by-step explanation: Speed is distance/time

18/3 = 6 miles per hour running

18/2 = 9 miles per hour biking

3 hour bike = 27 miles

1.50 hour run (0.50 because 30 minutes is half of an hour) = 9 miles

27 + 9/3 + 1.50 = 36/4.5 or 8