Aisha is considering how to allocate the next 6 hours of her free time. She could choose between leisure (L) and helping her neighbour with the house chores. If she decides to help her neighbour, she is going to get paid at 25 per hour, which she can then spend on her favourite pizza (P). Suppose the price of pizza is 12.50. Aisha's preferences for leisure and pizza are given by the following utility function: