During a road trip, Richard drove his car at 80mph for 1 hour, and then at 60mph for 2 hours. What was the average speed for the entire journey?
Total distance traveled = 80 (1) + 60 (2) = 80 + 120 = 200
Avg rate = Distance / Time = 200 / [ 1 + 2 ] = 200 / 3 = 66 + 2/3 mph
