Answer:
b. 60
Step-by-step explanation:
We have been given a formula [tex]5x+10y=800[/tex], where x represents the number of small vehicles and y represents the number of larger vehicles.
To find the number of small vehicles, we will substitute [tex]y=50[/tex] in the given equation as:
[tex]5x+10(50)=800[/tex]
[tex]5x+500=800[/tex]
[tex]5x+500-500=800-500[/tex]
[tex]5x=300[/tex]
[tex]\frac{5x}{5}=\frac{300}{5}[/tex]
[tex]x=60[/tex]
Therefore, 60 small vehicles were washed in total and option 'b' is the correct choice.