Answer:
The answer is: Yes, Bill's consumption decision is optimal.
Explanation:
Bill's marginal utility from consuming Pepsi is 2 units and Pepsi costs $1. So for every dollar Bill spends in Pepsi, he gets 2 units of utility.
Bill's marginal utility from consuming hamburgers is 6 units and each hamburger costs $2. So for every dollar Bill spends in hamburger, he gets 3 units of utility.
Bill's total budget is $12, and he gets 36 units of utility by consuming hamburgers. If he consumed Pepsi, he would get only 24 units of utility with the same budget.