1. Math Self Help Tutor:
EXPERIMENTAL PROBABILITY

2. Pennsylvania State Standard: Data Analysis and Probability

3. VOCABULARY
Experimental probability: A statement of probability based on the results of a series of trials.
E.G. You roll a six sided die 10 times and recorded that a 3 came up three times; a 1 came up two times; a 5 came up four times; and a 6 came up one time

4. HOW TO FIND EXPERIMENAL PROBABILITY
Experimental Probability:
P (event) = number of times event occurs
total number of trials

5. HOW TO FIND EXPERIMENTAL PROBABILITY
EXAMPLE PROBLEM: You have a bag of marbles. The bag contains 4 green marbles, 8 orange marbles, and 5 purple marbles. Pick a marble out of the bag, record the color that you picked, and then replace the marble. Do this 10 times and the find the probability that you pulled out a purple marble.
Since you are performing the experiment and recording your answers to find the probability, you are finding experimental probability.

6. HOW TO FIND EXPERIMENAL PROBABILITY
Trial
Green
Orange
Purple 1 2 3 4 5 6 7 8 9 10
TOTAL
Exp. Prob x
First, make a chart to record the results for your experiment
You pick out an orang marble the first time. So you put a check or an “x” to show the result.

7. HOW TO FIND EXPERIMENAL PROBABILITY
Trial
Green
Orange
Purple 1 2 3 4 5 6 7 8 9 10
TOTAL
Exp. Prob x x
For trial 2, you pick an orange marble again. Record your answer!

8. HOW TO FIND EXPERIMENAL PROBABILITY
Trial
Green
Orange
Purple 1 2 3 4 5 6 7 8 9 10
TOTAL
Exp. Prob x x
You pick a purple marble for trial 3. Record your answer! x

9. HOW TO FIND EXPERIMENAL PROBABILITY
Trial
Green
Orange
Purple 1 2 3 4 5 6 7 8 9 10
TOTAL
Exp. Prob x x
You pick a green marble for trial 4. Record your answer! x x

10. HOW TO FIND EXPERIMENAL PROBABILITY
Trial
Green
Orange
Purple 1 2 3 4 5 6 7 8 9 10
TOTAL
Exp. Prob x x
You pick a green marble for trial 5. Record your answer! x x x

11. HOW TO FIND EXPERIMENAL PROBABILITY
Trial
Green
Orange
Purple 1 2 3 4 5 6 7 8 9 10
TOTAL
Exp. Prob x x
You pick a purple marble for trial 6. Record your answer! x x x x

12. HOW TO FIND EXPERIMENAL PROBABILITY
Trial
Green
Orange
Purple 1 2 3 4 5 6 7 8 9 10
TOTAL
Exp. Prob x x
You pick an orange marble for trial 7. Record your answer! x x x x x

13. HOW TO FIND EXPERIMENAL PROBABILITY
Trial
Green
Orange
Purple 1 2 3 4 5 6 7 8 9 10
TOTAL
Exp. Prob x x
You pick a purple marble for trial 8. Record your answer! x x x x x x

14. HOW TO FIND EXPERIMENAL PROBABILITY
Trial
Green
Orange
Purple 1 2 3 4 5 6 7 8 9 10
TOTAL
Exp. Prob x x
You pick an orange marble for trial 9. Record your answer! x x x x x x x

15. HOW TO FIND EXPERIMENAL PROBABILITY
Trial
Green
Orange
Purple 1 2 3 4 5 6 7 8 9 10
TOTAL
Exp. Prob x x
You pick a green marble for trial 10. Record your answer! x x x x x x x x

16. HOW TO FIND EXPERIMENAL PROBABILITY
Trial
Green
Orange
Purple 1 2 3 4 5 6 7 8 9 10
TOTAL
Exp. Prob x x
Now find the total for each color by counting the marks in each column. x x x x x x x x 3 4 3

17. HOW TO FIND EXPERIMENAL PROBABILITY
Trial
Green
Orange
Purple 1 2 3 4 5 6 7 8 9 10
TOTAL
Exp. Prob x x
What is the probability that you pulled a purple? x x x x x x x x 3 4 3
# of times event occurred
total number of trials