Answer:
7 cars
Explanation:
The computation of the number of cars to be filled is shown below:
A car that is 90% full and the total people is 20 so 90% would be
= (.90)(20)
= 18
A car that is 65% full and the total people is 20 so 65% would be
= (.65)(20)
= 13
Now
Total number of people = (5)(18) + (3)(13).
= 129
Now the number of cars to be filled is
= 129 ÷ 20
= 6.45
= 7 cars