Expected Value Stat

• 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

• 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

Find the value of c

• 0.8

• 0.2

• 0.3

• 0.1

In a raffle, one ticket out of 250 will win a $280 prize, one ticket will win a $70 prize, one ticket will win a $70 prize, and one ticket will win a $30 prize. The other tickets will win nothing. If you have a ticket, what is the expected payoff?

• -$1.80

• $0

• $1.80

• $2

The table shows the probability distribution of a random variable X.

What is the standard deviation of X?

Round your answer to the nearest hundredth.

• 3.9

• 1.49

• 1.22

Expected value is

• an average.

• a predicted value of a game.

• the sum of the values multiplied by their probabilities.

• all of the above.

Find the expected value.

• 0.4

• 0.6

• 0

• 1.1

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

Suppose you buy a ticket for $6 out of a lottery of 1000 tickets where the prize for the one winning ticket is $800. What is the expected value (after paying for the ticket)?

• $800

• -$6.50

• -$6

• -$5.20

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. Do you expect to win or lose (on average)? How much?

• lose an average of $5.50

• lose an average of $1.50

• win an average of $2.00

• lose an average of $10.00