How many dollars does 3 bottles of water cost ?

Answer:
$7.5
Step-by-step explanation:
if we set up the proportion [tex]\frac{10}{4} =\frac{x}{3}[/tex] with cost on top and water bottles on bottom, we can divide 10/4 too get 2.5, which we can then multiply by 3 to get our x value, 7.5.