A van can carry 12 people and a bus can carry 20 people.
Step-by-step explanation
School A needed 7 more vans to carry 84 more students than School B. This means that we need to do 84 ÷ 7 = 12 students per van.
To find the amount of students per bus, we need to take the 12 people on the van from School B's 192 to get 180. We then do 180 ÷ 9 = 20 people per bus.