The language of probability Year 7 Maths

1. PROBABILITY
GETTING KNOWLEDGE READY

2. THE HOOK
• http://www.youtube.com/watch?v=QpfMwA0
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3. Learning Intentions for the Unit
•To understand the language of probability
•To be able to place events on a probability scale
•To be able to create a sample space
•To understand the language of simple probability
•To be able to calculate simple probability
•To understand the language of experimental
probability
•To be able to calculate experimental probability

4. Success Criteria
• I know what event, probability, certain, impossible and even chance mean.
•I can place events on a probability scale
•I can create a sample space for a given situation
•I can use a table to represent a sample space
•I know what outcome, favourable outcome and theoretical probability means
•I can calculate simple probability
•I know what trial, experiment, successful trial and experimental probability
means
•I can calculate the experimental probability
•I know the difference between experimental probability and actual probability

5. The Language of Probability
• Event – is a result that an outcome may occur
• Probability – is a value between 1 and 10 that
an event will occur
• Certain – means an event will occur and has a
probability of 1
• Impossible – means an event won’t occur and
has a probability of 0
• Even Chance – means there is a 50:50 chance
of the event occurring

6. Probability Scale
0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0
Impossible Very
Unlikely
Less than
even
chance
Highly
Unlikely
Even
Chance
Unlikely Likely
Better
than an
even
chance
Highly
Likely
Very likely Certain

7. Worked Example
• What is the chance you will compete in the next Olympics?
Step 1: Read the statement and pick the chance
of the event occurring and assign the
best word from the probability scale.
Step 2: Answer the question.
Answer: The chance of a you competing in the next
Olympics is very small, however it could
happen.
But it is unlikely that this will occur

8. What is the chance every student is year 7 will
obtain 100% in their maths test?
Answer: Due to each student having different
abilities and the high number of
students involved, it probably would
never happen.
It is impossible for this event to occur.

9. What is the chance that each person in your
class has been to the zoo?
Answer: This could be possible either with their
family or through the school. However
there may be some that haven’t been to
the zoo.
It is likely this event will occur.

10. What is the chance you flip a coin and tails
Comes up?
Answer: When you flip a coin there are only 2
possibilities, heads or tails. So there is a
50% chance of tails occurring.
There is an even chance that this event
will occur.

11. What is the chance that March is followed by
April?
Answer: This is a true statement. April always
follows March.
It is certain this event will occur

12. YOUR TURN TO PRACTISE
THE QUESTIONS IN YOUR
BOOKLETS
GOOD LUCK!