Bell Work

1. What’s the probability that the spinner will land on blue?

2. Samuel has a bowl of fruit containing 3 apples, 2 oranges and 5 pears. If he randomly picks 1 piece of fruit from the bowl, what is the probability it will be a pear or an apple?

12 3

4

567

8

Answers

apples3

2 oranges

5 pears+10 fruits total

1.

2.

Experimental Probability

Theoretical vs. Experimental Probability

Theoretical Probability:- It is how a probability of an event

“should” happen. Experimental Probability:- Experimental probability refers to the

probability of an event occurring when an experiment was conducted.

Theoretical Probability

There is a bag of blue, green and red chips. There is a 12% possibility of randomly picking a blue chip and a 25% chance of randomly picking a red chip. What is the probability of picking a green chip?Hint: Your three options are green, blue and red. Their probability will add up to 100%

Answer: 63%

Experimental probability

P(event) = number of times event occurs total number of trialsYou tossed a coin 10 times and recorded heads 3 times

and tails 7 times

P(head)= 3/10 , 0.3 or 30%

A head shows up 3 times out of 10 trials,

P(tail) = 7/10, 0.7 or 70%

A tail shows up 7 times out of 10 trials

HEADS

TAILS

Comparing experimental and theoretical probability

Both probabilities are ratios that compare the number of favorable outcomes to the total number of possible outcomes

P(head)= 3/10 or 30%

P(tail) = 7/10 or 70%P(head) = 1/2 or 50%

P(tail) = 1/2 or 50%

All results will add up to 100% every time!

Experimental Probability

You draw a marble out of the bag, record the color, and replace the marble. After 5 draws, you record 2 red marbles. According to your experiment what is the probability of drawing each color?

P(red)= 2/5, 0.4 or 40%

P(blue)= 3/5, 0.6 or 60%

EXAMPLE 2You roll a number cube 100 times. Your results are given in the table below. Find the experimental probability of rolling a 6. Write your answer as a percent.

P(rolling a 6) = 18100

Number of favorable outcomesTotal number of rolls

= 0.18 = 18%If you rolled the number cube 300 times then how many times would you predict that you would roll a 3 according to your experiment?

60 times300100

20 x

Rolled# of

times1 62 153 184 115 36 7

Results from rolling a six-sided die:

What is the experimental probability of rolling a 5? How does that compare to the theoretical probability?

Experimental:P(rolling a 5) = 3/60 = 1/20

Theoretical: P(rolling a 5) = 1/6

Experimental ProbabilityExampleA class group flipped a coin and recorded their results below.

What is their experimental probability of landing on heads?Solution

The group landed on heads 6 times, so the experimental probability is:

Trial: 1 2 3 4 5 6 7 8 9 10

Result: T H T H H H T T H H

6 3

10 5

successes

trials

Using the spinner below, what is the sample space? What is the probability that the spinner will land on “B” as a percentage?

A B

CD

E

A,B,C,D,E

1/5 = 20%

Practice:Experimental

Probability Worksheet