Question

ellen and tasha took a long bicycle trip last weekend.they rode the first 10 miles at a rate of 12 miles per hour. They realized they had to go faster to get to their destination before dark. So they sped up for the last 12 miles of the trip. The entire trip took 1 hour and 20 minutes. At what rate did they travel the last 12 miles? As mile per hours.

Answer 1

So, if we know that they rode the first 10 miles at the rate of 12 miles per hour, we know that they rode the first part in 50 minutes (10/12*60=50). This leaves half an hour to ride the next 12 miles. 12/(1/2)=24. So, if I didn't mess anything up, they should have traveled the last part at twice their initial speed, at 24 miles per hour.