Dec 4 - Discrete Probability Distributions

What value should go in the missing blank

(Start the answer with 0.)

What value should go in the missing blank

(Start the answer with 0.)

What value should go in the missing blank

(Start the answer with 0.)

What value should go in the missing blank

(Start the answer with 0.)

Which of the following is a discrete numerical variable?

• The number of students in a class.

• The height of a person.

• The weight of a car.

• Distance between two cities.

A food critic counted the number of menu items at each restaurant in town.

X is the number of menu items that a randomly chosen restaurant has. Write the probability distribution of X in the table below.

Write each probability as a decimal.

• 
• 
• 
• 

Is this a probability distribution?

• No, the sum of p(x) does not equal 1.

• Yes, all p(x) are between 0 and 1.

• No, all p(x) are not between 0 and 1.

• Yes, the sum p(x) is 1.

The table represents the probability of guessing correct on a 5 question true-false quiz.  Find the probability for at least 4 questions correct.

• .03125
• .15625
• .3125
• .1875

Choose the correct examples of discrete variable.

• A film critic's rating of a film (0 - 4 stars)

• The sum of the numbers rolled on a pair of dice

• Time taken to commute to work

• Winning ticket number drawn from a raffle

• Amount of gasoline a car

What is the difference between a discrete random variable and a continuous random variable?

• A discrete random variable takes all values in an interval of numbers while a continuous random variable has a fixed set of possible values with gaps between.
• A discrete random variable has a fixed set of possible values with gaps between while a continuous random variable takes all values in an interval of numbers.
• A discrete random variable takes only negative numbers while a continuous random variable takes both positive and negative numbers.
• A discrete random variable takes both positive and negative numbers while a continuous random takes only negative numbers.