PROBABILITY

GETTING KNOWLEDGE READY

THE HOOK

• http://www.youtube.com/watch?v=QpfMwA0z_1Y

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

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

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

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

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

What is the chance every student is year 7 willobtain 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.

What is the chance that each person in yourclass 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.

What is the chance you flip a coin and tailsComes 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.

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

YOUR TURN TO PRACTISE THE QUESTIONS IN YOUR

BOOKLETS

GOOD LUCK!