Car 1. (40 kph):
40 kph = 40,000 km per hour
Car 2. (15 mps)
15 mps x 60 (to get one minute) = 900 mpm
900 meter per minute
900 x 60 = 54,000 km
Therefore, car 2 is faster since it drives at 54km per hour and car 1 only travels at 40km per hour.
Also, you decide which car you want to choose.
Hope this helps! Have a great day.