1. What are the chances?
Statement of inquiry:
Patterns found in relationships can be
generalised to help us make
predictions for personal gain.
Inquiry questions:
Factual: How do we know what to expect?
Conceptual: Why does Mathematics sometimes overcomplicate simple problems?
Debatable: Is probability just for fun?
2. Probability
• LO: To be able to write probabilities
as fractions.
Notation: P(A) means the probability
of event A happening
09.06.2020
3. Probability Scale
What is the highest value &
lowest value which the
probability of an event can take?
5. number of outcomes
The probability of an event happe
wanted
total
ning =
number of outcomes
0
Impossible
1
Certain
½
Getting a tail when
tossing a coin.
Getting a 3 when you
throw a die.
Being born in the
month of March.
2
1 3
Choosing a red cube at
random from the bag.
4 6
Choosing a blue bead at
random from the bag.
5
5
5
4
Getting a 5 on the
spinner.
5
1
2
1
6
1
12
5
12
3 9
4 12
11
12
6. 1
Jenny has 12 cards with different shapes on
as shown. She turns the cards over and
chooses one at random.
(a) P(red shape)
(b) P(triangle)
(c) P(3D shape)
(d) P(quadrilateral)
(e) P(not a 3D shape)
(f) P(shape which is not blue)
2/12
3/12
9/12
10/12
4/12
7. 0
Sam has 6 cards with numbers on as shown. He
turns the cards over and chooses one at
random.
Work out the probability that:
(a) P(odd number)
(b) P(square number)
(c) P(prime number)
(d) P(a multiple of 12)
3/6
1/6
4/6
2/6
9
16
3
12
144
1
(e) P(a factor of 9) 3/6
8. Classwork
• Pg 249 – 250 Ex 12A
Q3, Q4, Q5*, Q6*, Q7*
LO: To be able to write probabilities as
fractions.
