On a trip to visit friends, a family drives 65 miles per hour for 208 miles of the trip. if the entire trip was 348 miles and took 6 hours, what was the average speed in miles per hour, for the rest of the trip?

From information given, we know
208 miles was at rate of 65 mph. so divide total mileage by speed to get time spent.

208 ÷ 65 = 3.2 hours

So the rest of the trip took 6 - 3.2 = 2.8hours to travel another 348 total miles minus the 208 miles driven at 65mph is 140 miles.

140 miles divided by 2.8 hours gives speed

140 ÷ 2.8 = 50 miles per hour

20000 as first it increases by 2500 then by 5000 so next it will increase by 10000