Probability

Vocabulary

100

Melanie rolls an 8-sided number cube and it lands on 7. What is the action?

Rolling the number cube

200

Melanie rolls an 8-sided number cube once. What is the sample space?

1, 2, 3, 4, 5, 6, 7, 8

300

In probability, what is the term for a possible result of an action?

Outcome

400

Niko rolls a six-sided number cube 300 times and uses the data to estimate that the probability of rolling a 6 is 15%. TWO PART QUESTION 1. Is this an example of (A) experimental probability or (B) theoretical probability? 2. How many times out of 150 did he actually roll a 6?

1. A 2. 45

500

Patty plans to flip a coin 250 times. She predicts that she will flip heads 125 times. TWO PART QUESTION 1. Did Patty use (A) experimental probability or (B) theoretical probability? 2. What would the relative frequency of flipping heads be if Patty turned out to be right?

1. B 2. 0.5 (or 1/2 or 50%)

Likelihood

100

There is a 10% chance of rain this weekend. Would you describe the likelihood as impossible, unlikely, as likely as not, likely, or certain?

Unlikely

200

Would you describe the likelihood of flipping a fair coin and getting tails as impossible, unlikely, as likely as not, likely, or certain?

As likely as not

300

According to your data, the experimental probability of selecting a blue marble from a bag of marbles is 0.75. Would you describe the likelihood as impossible, unlikely, as likely as not, likely, or certain?

Likely

400

Would you describe the likelihood that it snows in Death Valley tomorrow as impossible, unlikely, as likely as not, likely, or certain?

Impossible

500

Would you describe the likelihood that the student with the highest score on Mr. Babbitt's quiz is a seventh grade student as impossible, unlikely, as likely as not, likely, or certain?

Certain

Experimental Probability

100

Jonny flips a coin 10 times and gets the following results: heads, heads, tails, heads, tails, heads, heads, tails, heads, heads What is the experimental probability of flipping tails?

three tenths (3/10)

200

Maggie rolls a 6-sided number cube and gets the following results: 1, 4, 1, 3, 6, 5, 3, 2. What is the experimental probability of rolling an even number?

three eighths (3/8)

300

You perform a probability experiment with a spinner with equal-sized sections labeled 1-4. The results for 20 trials are: Spin a (1) - 8 times Spin a (2) - 3 times Spin a (3) - 5 times Spin a (4) - 4 times What is the experimental probability of spinning a 2? (Answer MUST be in decimal form)

3/20 = 0.15

400

You roll an 8-sided number cube 150 times with the following results: Roll a (1) - 21 times, Roll a (2) - 20 times, Roll a (3) - 19 times, Roll a (4) - 18 times, Roll a (5) - 16 times, Roll a (6) - 17 times, Roll a (7) - 24 times, Roll an (8) - 15 times. What is the experimental probability of rolling a number greater than 2 but less than 7?

70/150 = 7/15 or 0.466666... or 46.6666...%

500

You repeatedly roll a 6-sided number cube with the following results: Roll a (1) - 49 times, Roll a (2) - 57 times, Roll a (3) - 38 times, Roll a (4) - 51 times, Roll a (5) - 57 times, Roll a (6) - 48 times. What is the experimental probability of rolling an even number?

156/300 = 52/100 = 26/50 = 13/25 or 0.52 or 52%

Theoretical Probability

100

What is the theoretical probability of rolling a 2 on a six-sided number cube?

1 out of 6 (1/6)

200

What is the theoretical probability of rolling less than a 5 on a six-sided number cube?

4/6 (four sixths) or 2/3 (two thirds)

300

You spin a spinner with equal-sized sections colored green, blue, red, purple, black, white, yellow, and orange. What is the theoretical probability of spinning a color that starts with 'B'?

2/8 (two eighths) or 1/4 (one fourth)

400

Keith has a bag of marbles that contains 4 blue marbles, 11 red marbles, and 10 green marbles. What is the theoretical probability of selecting a red marble? (Answer MUST be in decimal form)

11/25 = 0.44

500

Megan has a bag of marbles that contains 7 purple marbles, 6 blue marbles, 8 red marbles, 9 yellow marbles, and 10 green marbles. She plans to do an experiment with 200 trials where she takes out a marble, checks the color, and puts it back. Based on the theoretical probability, how many times do you expect her to take out a purple marble?

35

Probability Model

100

What are the three parts of a probability model?

1. the action 2. the sample space 3. a list of events with their probabilities

200

Action: Flipping a coin Sample Space: heads, tails Complete the probability model.

P(heads) = 0.5, P(tails) = 0.5

300

Action: ? Sample Space: ? P(1) = 1/6, P (2) = 1/6, P(3) = 1/6, P(4) = 1/6, P(5) = 1/6, P(6) = 1/6 Complete the probability model

Action: Rolling a 6-sided number cube Sample Space: 1, 2, 3, 4, 5, 6

400

A spinner has 5 equal-sized sections labeled "1", "2", "3", "4", and "5". Write a probability model for spinning the spinner.

Action: Spin the spinner Sample Space: 1, 2, 3, 4, 5 Probabilities: P(1) = 20%, P(2) = 20%, P(3) = 20%, P(4) = 20%, P(5) = 20% ** 20% = 0.2 = 1/5 **

500

Write a probability model to find the probability that a student will choose each type of music. Question: "What type of music is your favorite?" Responses: Country (9), Rock (18), Pop (33), Rap (24), Hip-Hop (16)

Action: Asking "What type of music is your favorite?" Sample Space: Country, Rock, Pop, Rap, Hip-Hop Probabilities: P(Country) = .09, P(Rock) = .18, P(Pop) = .33, P(Rap) = .24, P(Hip-Hop) = .16 ** Fractions (e.g. 9/100) or Percents (e.g. 9%) are also acceptable **