Probability Distribution Expected Value

Given the probability model in the table below, what is the expected value of the random variable?
  X        50          20        5
P(X)     0.1         0.3      0.6

• 14

• 4.67

• 5

• 7.5

The table above shows a television station's advertisement sales. The distribution of sales for one 24-hour day is given. Solve for the mean (Expected Value). Round to the nearest hundredth.

• 31.80

• 15.68

• 0.20

• 1.00

Choose an American household at random. What is the expected number of cars for that household?

• 1.75

• 1.84

• 2.00

• 2.50

A small store keeps track of the number X of customers that make a purchase during the first hour that the store is open each day. Based on the records, X has the following probability distribution. What is the average number of customers that the owner can expect to make a purchase in the first hour of opening?

• 0.2

• 1.4

• 2.0

• 3.0

Find the mean (expected value) of the probability distribution.

• 85

• 83.2

• 87.1

• 84.4

Data was compiled and the number of goals for a hockey team per game and the corresponding probabilities are given below. If this hockey team plays an 82-game season, what is the expected cumulative goal total for the next season?

• 220

• 239

• 261

• 309

• 320

A student group sells 500 raffle tickets for $2 each. At the drawing the top prize will be a gift certificate for $100. Second prize will be a $50 gift card and there will be five 3rd prizes, each a $20 gift card. What is the expected value of a ticket?

• lose an average of $5.50

• lose an average of $1.50

• win an average of $2.00

• lose an average of $10.00

• -$2.50

• -$3.33

• $0

• $5

A quiz game has three questions. Each correct answer scores 5 points, and each wrong answer scores 0 points. If a player guesses all answers, assuming a 50% chance of getting each question right, what is the expected score?

• 7.5

• 10

• 12.5

• 15

A stockbroker estimates that at the end of the year, there is a 40% chance a stock will be worth $50, a 35% chance it will be worth $60 and a 25% chance it will be worth $70.
What expected value does this broker assign to this stock's end-of-the-year price?

• $58.50

• $60.00

• $62.50

• $65.00