Answer: 20 km/h
Explanation:
Speed = Distance / Time
Heon Train:
Translate minutes to hours:
90 minutes = 1.5 hours
= 120 / 1.5
= 80 km/h
Ami's Train
Train leaves at 11:25 and arrives at 15:10.
15:10 - 11:25 = 3hours 45 minutes
3 hours 45 minutes in minutes = (60 * 3) + 45 = 225 minutes
225 minutes in hours is = 225/60 = 3.75 hours
Speed of train = 375 / 3.75
= 100 km/h
Difference between average speeds:
= 100 - 80
= 20 km/h