Gabriella drives for 40 miles at 60 miles per hour, 20 miles at 40 miles per hour, and 10 miles at 56 miles per hour. Her overall average speed is 40 miles per hour. If she drove for another __ miles at ___ miles per hour, then her overall speed would be ___ miles per hour.
Distance Speed Time
40 mi 60 mi/hr 40/60 hr 40.0 min
20 mi 40 mi/hr 20/40 hr 30.0 min
10 mi 56 mi/hr 10/56 hr 10.7 min
totals 70 mi 80.7 min = 1.345 hr
avg speed 70 mi / 1.345 hr = 52.04 mi/hr
Gabriella takes another drive, added at the bottom of the table.
Distance Speed Time
40 mi 60 mi/hr 40/60 hr 40.0 min
20 mi 40 mi/hr 20/40 hr 30.0 min
10 mi 56 mi/hr 10/56 hr 10.7 min
60 mi 80 mi/hr 60/80 hr 45.0 min
totals 130 mi 125.7 min = 2.095 hr
avg speed 130 mi / 2.095 hr = 62.05 mi/hr
