Statistics - Unit 6 - Random Variables

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

Tags

CCSS.HSS.MD.A.2

If the expected value is negative, are you expected to win?

• yes
• no

Tags

CCSS.HSS.MD.A.2

Eva flips a coin. If she gets heads, she wins $4. If she gets tails, she loses $3. What is her expected value of a coin flip?

• $1

• $0.50

• -$0.50

• $0

Tags

CCSS.HSS.MD.B.5A

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

• 85

• 83.2

• 87.1

• 84.4

Tags

CCSS.HSS.MD.A.2

• Yes, because all of the probabilities are between 0 and 1 inclusive and the sum of all the probabilities is 1.
• No, all probabilities are not be between 0 and 1 inclusive
• No, the sum of all the probabilities is not 1.
• Yes, because the distribution is symmetric

Tags

CCSS.7.SP.C.7B

• Yes, because all of the probabilities are between 0 and 1 inclusive and the sum of all the probabilities is 1.
• No, all probabilities are not be between 0 and 1 inclusive
• No, the sum of all the probabilities is not 1.
• Yes, because the distribution is symmetric

Tags

CCSS.HSS.MD.A.3

CCSS.HSS.MD.A.4

• Yes, because all of the probabilities are between 0 and 1 inclusive and the sum of all the probabilities is 1.
• No, all probabilities are not be between 0 and 1 inclusive
• No, the sum of all the probabilities is not 1.
• Yes, because the distribution is symmetric

Tags

CCSS.HSS.MD.A.3

CCSS.HSS.MD.A.4

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

Tags

CCSS.HSS.MD.A.2

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

Tags

CCSS.HSS.MD.A.2

Discrete data is

• countable

• measurable