1) Draw and label a probability scale.
2) List 3 things that we can classify as an “unlikely” event.
3) Assign a value of 0 to 1 of the probability of you having a
job one day.4) Write 4/9 as a decimal and percentage (no calculators).5) What has a greater value, 11/13 or 7/9 (no calculators)?
Review…
Probability Scale…
Impossible CertainEvenChance
Not likely Likely
Relative Frequency in
experiments…Relative
Frequency =
Outcome Frequency
Total Frequency
(all experiments)
Relative Frequency Table…
III12
3
4
5
6
3 =3÷15 = 0.2
1.0
Fill out the relative frequency tables on your graphic
organizer for 5, 25, and 50 dice rolls.
Relative Frequency Table…
IIIII
I
III
IIII
I
12
3
4
5
6
32
1
3
5
1
=3÷15 = 0.2=2÷15 =
0.133=1÷15 = 0.0667=3÷15 =
0.2=5÷15 = 0.333=1÷15 =
0.0667IIII IIII IIII 15 1.0
As relative frequency
experiment trials get closer to
infinity…
Theoretical Probability.
Sample Space
Tree Diagram…
P
123456
Sample Space
S = {…} Example: a bag of skittles…S = {yellow, orange, green,
purple, yellow}n(s) = 5
Pg. 401 # 1-7
What is a favourable outcome?
Simple Probability
P(event) =
# of favourable outcomes
# of total outcomes
How does this compare to the relative frequency formula???
Example…
P(1,2) = 2
6
1
3=
Pg. 404 # 1-9
Conclusion…
We can use relative frequency tables for experimental
probability, but using simple probability is more accurate
and efficient.