There are 12 more cars than trucks in a parking garage. The ratio of trucks to cars is 3 : 5. How many trucks and how many cars are in the parking garage?
We could solve this with some unknowns.
Let's say C is the # of cars, and T is the # of trucks.
We know that C = 12 + T, and T : C = 3 : 5.
As T / C = 3 / 5, we can cross multiply to get that 5T = 3C.
So, C = 12 + T, and 5T = 3C. I hope you can solve this on your own now!
In case you want to check, here's the solution.
Substitute (12 + T) into 5T = 3C
5T = 3(12 + T)
Distribute to get:
5T = 36 + 3T
Isolate the variable: 5T - 3T = 36
2T = 36
Divide by 2, and te number of trucks is 18.
The number of cars is 12 + 18, which is 30.
:)