distance covered in first leg = 2(45) or 90 km
so total distance = 180 km
wants to average 60 mph
total time = 180/60 = 3
so he must cover the last 90 km in 1 hour or his speed must be 90 kmh.
Sam drove for 2 hours at 45mph. He has the same distance remaining. How fast should he drive to make his average speed 60mph.
1 answer