Answer:
36 bottles for $4
Explanation:
First you need to calculate the price for one bottle, the lower the cost, the better buy. Do this by dividing the price by the amount of bottles:
= $3 ÷ 24
= 0.125 cents
= $4 ÷ 36
= 0.111 cents
The cheaper option and the better buy is the 36 bottles for $4.