Answer:
$7.5 Dollars
Explanation:
The cost of 4 bottles is $10. So, 1 bottle is going to be $2.50 (division)
Now, to find the cost of 3 water-bottles, we have to multiply.
$2.50 * 3 = $7.50.
So, the answer to this question is 3 bottles = $7.50
(Hope this helps!)