Representing Sample Space

​Sample Space

The sample space is a list of all the possible outcomes of a random experiment.

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Math 7 | Probability

​ex. The sample space of flipping a coin is:

• Heads

• Tails​

Multiple Choice

What is the sample space when rolling a regular number cube?

• 1

• 2, 4, 6

• 1, 2, 3, 4, 5, 6

• 6

Multiple Choice

What is the sample space for the jar of marbles?

• red

• red, yellow, green, blue

• red and yellow

• red and green

Multiple Choice

What is the sample space when choosing one month out of the year?

• Jan., Feb., Mar., April, May, June, July, Aug, Sept, Oct., Nov., Dec.

• Jan., Mar., April, May, June, July, Sept, Oct., Nov., Dec.

• 12 months

• 52 weeks

Probability

4/13/21

So far we know the following

• Sample Space: is the set of all possible outcomes.

• Three ways to represent a sample space are: to list the possible outcomes, to create a tree diagram, or to create a Venn diagram.

• Event is any combination of outcomes. Upper case letters like A and B represent events.

• P(A) = 0 means the event A can never happen. 

• P(A) = 1 means the event A always happens. 

• P(A) = 0.5 means the event A is equally likely to occur or not to occur.

​Probability - the chance that something will occur.

Math 7 | Probability

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​Examples:

​What is the probability of the spinner landing on orange?

​What is the probability of the spinner landing on blue?

Multiple Choice

Mrs. Trevino has 3 red pens, 5 pink pens, and 8 blue pens. What is the probability that she will choose a blue pen to grade papers?

• 1/2

• 8

• 3/16

• 16/8

Multiple Choice

To play a game Benny must spin the spinner shown below. 

          What is the probability that the spinner will land on a number less than 7?

• 7/8

• 3/4

• 8/7

• 0

Ex. There are 4 red, 3 purple, and 2 pink jellybeans.

What's P(pink or red)?

Possible out of total= 6/9

Reduce to 2/3

Multiple Choice

What does P(A) = 0.5 represent?

• Event A is equally likely to occur or not to occur.

• Event A will never occur

• Event A will always occur

Multiple Choice

What does P(A) = 1 represent

• Event A can never happen

• Event A is equally likely to occur or not to occur.

• Event can always happen

Multiple Choice

Probabilities are between zero and one.

What does P(A) = 0 represent?

• event A can always happen

• event A can never happen

• event A is equally likely to occur or not to occur.