A driver sets out on a journey. For the first half of the distance she drives at the leisurely pace of 30 mph; she drives the second half at 60 mph. What is her average speed for the trip. Solve the problem algebraically using the formula D=r*t.
A driver sets out on a journey. For the first half of the distance she drives at the leisurely pace of 30 mph; she drives the second half at 60 mph. What is her average speed for the trip. Solve the problem algebraically using the formula D=r*t.