Answer:
45 km/h
Step-by-step explanation:
In the first part of the trip, he already covered 30 km so we can subtract that from the total distance
45 - 30 = 15
This means he has 15 km to go
He also took an hour, or 60 minutes, to get to school. We subtract the time spent of the first part and time spent talking to a friend from the 60 minutes
60 - 35 = 25
25 - 5 = 20
He took 20 minutes to cover the second part of the journey
Speed = distance/time
15/20 = 0.75
He covered 0.75 km per MINUTE
to find it in km/h, we just multiply the number by 60
0.75 x 60 = 45
