MA.8.2.1 MA.8.2.2 MA.8.2.3

Probability 8th Grade

Florida - Benchmarks for Excellent Student Thinking: MA.8.2.1
Determine the sample space for a repeated experiment.
Florida - Benchmarks for Excellent Student Thinking: MA.8.2.2
Find the theoretical probability of an event related to a repeated experiment.
Florida - Benchmarks for Excellent Student Thinking: MA.8.2.3
Solve real-world problems involving probabilities related to single or repeated experiments, including making predictions based on theoretical probability.

Probability is a measure of the likelihood of an event occurring.

Probability of event occurring = \frac{number of ways event can occur}{total number of possible outcomes}

The sample space of an event occurring is the set of possible outcomes.

The complement of an event occurring is the event not occurring.
If the probability of an event occurring is P(A), then the complement is 1 − P(A), often denoted as P(A').

What is the probability Haley selects a blue token?

\begin{array}{rcl} Probability of event occurring & = & \frac{number of ways event can occur}{total number of possible outcomes} \\ = & \frac{7}{2 + 7 + 3} \\ = & \frac{7}{12} \end{array}

What is the probability Haley does not select a blue token?

The probability of an event not occurring is 1 minus the probability of the event occurring.

1 - \frac{7}{12} = \frac{5}{12}

Experimental probability is a measure of the
likelihood of an event occurring based on trials.

Experimental Probability = \frac{number of trials where event occurs}{total number of trials}

\begin{array}{rcl} Experimental Probability & = & \frac{number of trials where event occurs}{total number of trials} \\ = & \frac{6}{25} \end{array}

Probability can be used to make approximate predictions.

The spinner is divided into 6 equal sections, so the probability the spinner lands on each section is

\frac{1}{6}

Multiply

\frac{1}{6}

by 300 to predict the number of times the spinner will land on each section.

\frac{1}{6} \times 300 = 50

Since 50 is

\frac{1}{6}

of 300, the spinner would land on each section approximately 50 times.

Because this is a prediction, the spinner would probably not land on each section exactly 50 times.

Probability

Florida - Benchmarks for Excellent Student Thinking: MA.8.2.1

Determine the sample space for a repeated experiment.

Florida - Benchmarks for Excellent Student Thinking: MA.8.2.2

Find the theoretical probability of an event related to a repeated experiment.

Florida - Benchmarks for Excellent Student Thinking: MA.8.2.3

Solve real-world problems involving probabilities related to single or repeated experiments, including making predictions based on theoretical probability.

Processing Request...