Flashcard 8.1 Practice

Front

What is a discrete random variable?

Back

A discrete random variable is a variable that can take on a countable number of distinct values. For example, the number of siblings a person has is discrete.

Front

What is a continuous random variable?

Back

A continuous random variable is a variable that can take on an infinite number of values within a given range. For example, the height of a plant can vary continuously.

Front

What does expected value mean in probability?

Back

Expected value is the average value of a random variable, calculated as the sum of all possible values, each multiplied by its probability of occurrence.

Front

How do you calculate the expected value of a discrete random variable?

Back

To calculate the expected value, multiply each possible value by its probability and sum all these products.

Front

What is the expected value of a raffle ticket that costs $1 and has a 1 in 1000 chance of winning $50?

Back

The expected value is -$0.95, meaning on average, ticket owners lose $0.95 per ticket.

Front

Classify the following: The number of students in a classroom.

Back

Discrete.

Front

Classify the following: The amount of milk in a jug.

Back

Continuous.

Front

What is the expected value of a stock with a 40% chance of being worth $50, a 35% chance of $60, and a 25% chance of $70?

Back

The expected value is $58.50.

Front

What is the significance of a negative expected value in a game of chance?

Back

A negative expected value indicates that, on average, players will lose money over time.

Front

Give an example of a situation with a discrete random variable.

Back

The number of cars sold by a dealership in a month.