Answer:
3 trips
Step-by-step explanation:
First subtract the initial trip of 8 km from 22 to get 14.
Then divide 14 by 7 to get the additional number of trips he will need to take (2 additional trips)
So with the first trip of 8 km and the 2 trips of 7 km, it will take him 3 trips to go 22 km