Question

Car travels 2 miles. It travels 15 mph for the first mile. How fast did it travel during the second mile so the average speed is 30 mph?

Answer 1

V = S / t = (15 mph * 1 hr + V2 * 1 hr) / 2 hr = 30 mph * 2 hr

V = (15 + V2) / 2 = 30 V = 30

60 = 15 + V2

V2 = 45 mph

Check:

Distance = 15 + 45 = 60

Total time = 2

Avg speed = 60 / 2 = 30