When you find the sum of 3 and 5 you get 8, which represents the total number of vehicles used in the trucks to cars ratio.
This means that the ratio of cars to total vehicles in this ratio is 5 to 8. Because there are 24 vehicles in the parking lot, and 8 × 3 = 24, you can multiply the entire ratio by three to get your answer:
5 to 8 ⇒ 15 to 24
Therefore, the number of cars in the parking lot is 15.
