5.5 Reflections

Poll

Bet $300,000 of your money to earn $1,000,000?

• Yes

• No

Multiple Choice

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

• yes
• no

Multiple Choice

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

Multiple Choice

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

Multiple Choice

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

• 85

• 83.2

• 87.1

• 84.4

Multiple Choice

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

Multiple Choice

• 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

Multiple Choice

An event is DEPENDENT, if...

• The first event has no affect on the next event

• The first event affects the second event

Multiple Choice

Is the event INDEPENDENT or DEPENDENT?

Amy plays card games. She picks a card at random. Then without putting the first card back, he picks a second card at random.

• Independent

• Dependent

Multiple Choice

A jar contains 4 white playing chips, 5 purple chips, and 1 black chip. Chips are selected randomly one at a time, and are not replaced. Find P(purple then black)

• 1/18

• 2/5

• 3/7

• 4/9

Multiple Choice

A box contains 5 purple marbles, 3 green marbles and 2 orange marbles. Draws are made without replacement. Find P(both marbles are purple)

• 2/9

• 1/3

• 1/2

• 1/4

Multiple Choice

Given the person is a child, what is the probability they would pick neither?

• .26
• .195
• .286
• .214