It took Esteban 1 minute and 20 seconds to travel one mile. If he then drives this one mile distance in 55 seconds, how much faster is he driving in miles per hour?

Answer 1

60(4/3 min.)*1 mile = 80 mph

(55/60 min)60 * 1 mile = 55 mph

Answer 2

the times are 80 seconds and 55 seconds
1mi/80s * 3600s/hr = 45 mi/hr
1mi/55s * 3600s/hr = 65.45 mi/hr

Now just subtract