Discrete Random Variables Expected Value

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

In a certain community, 30% of households have 1 child, 43% have 2 children, and 27% have 3 children. If a household is selected at random, what is the expected number of children in that household? HINT: A Probability table may be helpful.

• 2.00

• 2.13

• 1.97

• 1.27

The table above shows the number of cell phones per household in a small town. Find the mean round to the nearest hundredth.

• 2.80

• 2.93

• 0.10

• 0.14

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. Round to the nearest hundredth.

• 31.8

• 15.68

• 0.20

• 1.00

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

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

• 85

• 83.2

• 87.1

• 84.4

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 following table shows the probability distribution for the number of children in each family in the town of Crossville. What is the average number of children in this town?

• 1.9

• 0.3

• 2.1

• 3

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

The number of hybrids sold by a salesman and the probabilities of selling that many are given in the table. How many hybrids do we expect the salesman to sell in a week?

• 1.85

• 1.53

• 1

• 1.92