Mary is currently buying apples and oranges such that the last unit of apples has 30 units of utility and the last unit of oranges has 40 units of utility. She has allocated her entire budget. If the price of an apple is 10 cents and the price of an orange is 20 cents, to maximize her utility, what should Mary do

Buy more apples and fewer oranges

Explanation:

Utility is defined as the level of enjoyment or satisfaction that a person gets from consumption of a good or service.

Consumers logically try to maximise utility.

In the given instance we need to get the level of utility for apples and oranges to see which has more utility per unit cash spent.

For apples utility per cash spent = 30 units of utility ÷ 10 cents= 3 utility per cent

For oranges utility per cash spent = 40 units of utility ÷ 20 cents = 2 utility per cent

As apples have a higher utility per cent spent, it will be best Mary buys more apples and fewer oranges

reducing the scale of the market for a new product.