Expected Value

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

Find the expected value. READ CAREFULLY!

• 4.5

• 25.5

• 3.825

• 6.52

Find the expected value

• Loss of $0.875

• Loss of $2.125

• Win of $1.875

• Win of $3.125

A car dealer buys hybrids for $21,000 each and sells them for $24,500 each. Find his expected weekly profit.

• $2,380

• $5,355

• $8,109

• $37,485

Expected value is

• an average.

• a predicted value of a game.

• the sum of the values multiplied by their probabilities.

• all of the above.

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 game involves rolling a colored die with three red sides, two green sides, and one blue side. A roll of a red loses. A roll of green wins $2.00. A roll of blue wins $5.00.  The charge to play the game is $2.00. What is the expected value

• $0

• -$0.50

• $.67

• $-1.50

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

• yes

• no

Suppose you pay $1.00 to roll a fair die with the understanding you will get $3.00 back rolling a 4 or a 2, and nothing otherwise.  What is the expected amount you win?

• $0.00

• -$1.00

• $1.00

• $3.00