EXPERIMENTAL PROBABILITYGoal: to find the experimental probability of an event happening.

EXPERIMENTAL PROBABILITY In experimental probability, the

likelihood of an event is estimated by repeating an experiment many times and observing the number of times the event happens. That number is divided by the total number of trials.

The more the experiment is repeated, the more accurate the estimate is likely to be.

TO FIND EXPERIMENTAL PROBABILITY:

number of times an event occurstotal number of trials

EXAMPLE #1: A marble is drawn out of a bag and then

replaced. The table shows the results after 100 draws. Estimate the probability of

drawing a yellow marble.Outcome

Green

Red Yellow Blue White

Draws 30 18 18 21 13number of yellow marbles drawn

total number of draws

EXAMPLE #2: The table shows the results of 500

spins of a spinner. Estimate the probability of the spinner landing on 2.

Outcome 1 2 3Spins 151 186 163

EXAMPLE #3: A researcher polled 230 freshman at a university and found that 110 of them were enrolled in a history class. Estimate the probability that a randomly selected freshman is enrolled in a history class.

EXAMPLE #4: Tim has made 65 out of his last 150 free throw attempts. Estimate the probability that he will make his next free throw.

EXAMPLE #5: The table shows the results

when players were up to bat. Estimate the probability of each event.

A batter hits a single

A batter hits a double

A batter hits a triple

A batter makes an out

Result Numbers

Single 13Double 10Triple 3Home run

2

Walk 4Out 18Total 50

EXAMPLE #6: A researcher has been observing cars passing through

an intersection during heavy traffic. Of the last 50 cars, 21 turned left, 15 turned right, and 14 went straight. Estimate the probability that a car will turn right.

If 200 more cars came through the intersection, how many would go straight?

Outcome Left turn Right turn StraightObservations

21 15 14

EXAMPLE #7: Ed polled 128 students

about their favorite hobbies.

Use the table to compare the probability that a student’s favorite hobby is sports to the probability that it is reading.

Favorite

Hobby

Number of

StudentsMovies 36

Sports 32

Reading

32

Video games

28

EXAMPLE #8: Use the table to compare

the probability that the Huskies will win their next game with the probability that the Knights will win their next game.

Team Wins Games

Huskies

79 138

Cougars

85 150

Knights

90 146