Answer:
56 cars.
Step-by-step explanation:
The cost of wash of each car = $12
Total amount collected = $672
Let the number of cars wash = x
Hence, in order to find the numbers of total car washed, we can make below proportion
[tex]\frac{1}{12}=\frac{x}{672}[/tex]
On solving for x, we get
[tex]x=\frac{672}{12}\\\\x=56[/tex]
Thus, the deal washed 56 cars.