math
posted by anonymous .
andys average driving speed for a 4hour trip was 45 miles per hour. during the first 3 hours he drove 40 miles per hour. what was his average speed for the last hour of his trip?
The trip length was 4 x 45 = 180 miles. He went 3x40 = 120 the first three hours. How many miles does that leave for the last hour?
4+5

A car driver completes a 180km trip in 4hour. If he averages 50km/h during the first 3 hour of t