Expected Probability

Determine which of the following distribution is NOT a probability distribution.

• A

• B

• C

• D

Is this a probability distribution?

• No, the sum of p(x) does not equal 1.

• Yes, all p(x) are between 0 and 1.

• No, all p(x) are not between 0 and 1.

• Yes, the sum p(x) is 1.

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

• 31.7
• 34.1
• 63.4
• 68.2

Find the expected value. READ CAREFULLY!

• 4.5

• 25.5

• 3.825

• 6.52

Sam’s pencil case contains 3 red, 2 blue and 5 black pens. He takes a pen out without looking then puts it back 500 times. Roughly how many times would you expect him to pick up a blue pen?

• 50

• 100

• 200

A spinner has 5 sections with the following numbers on it:

3 4 4 5 6

Each section is equally likely.

It is spun 75 times.

Roughly how many times would you expect him the spinner to land on 4?

• 5

• 15

• 25

• 30

If I spin 35 times, how many times should the color yellow show up?

• 1

• 5

• 7

• 10

You spin each spinner once. You get $50 if you spin a 2 and a vowel. You get $25 if you spin a 2 and a consonant. You get $5 if you spin a 1 and a vowel. Everything else earns $0. What is the expected value of this game?

• $80

• $8.75

• $10.25

• $12.50

A fair, 6-sided dice is thrown 120 times.

Roughly how many times would you expect the number 5 to come up?

• 6

• 10

• 12

• 20