Question

A cafeteria has four different meal options: chilli, stew, pizza and curry. Each customer eats one type of meal. The probabilities of a customer chosen at random eating each type of meal are shown in the table below. Yesterday, Sumaya chose 300 customers at random and asked them which meal they ate that day. How many of these customers would you expect to have eaten curry?

Meal Probability
Chilli 15%
Stew 0.3
Pizza 1/10
Curry ?

Answer 1

You would expect 0.125 (or 12.5%) of the 300 customers chosen at random to have eaten curry.

In probability theory, the expected value is a measure of the center of a probability distribution. In this context, it represents the average number of customers you would anticipate choosing curry out of a sample of 300 customers. The probability of each meal option reflects the likelihood of a customer selecting that particular meal.

For curry, with a probability of 1/10 or 10%, multiplying this probability by the total number of customers (300) gives the expected count of customers who chose curry, which is 30. This means that, on average, you would predict 30 customers out of the 300 surveyed to have chosen curry based on the provided meal probabilities. Understanding the expected values helps in making statistical inferences and predictions about the behavior of a random variable within a given population or sample.