We are given:
The ratios of the number of hybrid vehicles to the total number of vehicles in the lot over a weekend (3 days) are equivalent.
This means that if on day 1, 100 hybrid cars parked and there are 300 cars in total, the ratio is 1 is to 3.
Therefore, on day 2 and 3, we can determine the number of hybrid cars parked given the total number of cars parked using the ratio, and vice versa.