You want to maximize your utility and find your consumer optimum.

Here is a table of your current situation:

Taco Bell drink: $1.00

Taco Bell burrito supreme: $5.00

Income: $11.00

DrinkTotal UtilityBurrito supremeTotal Utility

0000

1 100 1600

2220 2 1100

3280 3 1500

4330 41600

53505 1650

Calculate the Marginal Utility then the MU/P to find Consumer Optimum.

How many drink(s) and burrito supreme(s) should you purchase to reach consumer optimum?