



 
Marylyne, Average speed is total distance divided by total time. You don't know the distance from home to school so let it be d miles. You drive at 70 miles per hour which is 1/70 hours/mile. The distance you drive is d miles so it takes you d × 1/70 = d/70 hours to drive to school. How long did it take you to drive home form school? What was your total time? What was the total distance? What was your average speed? Penny  


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