Lesson

Do you remember how to describe the likelihood of an event happening?

Which section describes the chance of 'the next person you meet has the same birthday as you'?

A

B

Worked Solution

Idea summary

We can represent likelihood like a number line. We start with impossible events on the left and as we move right the events are more likely.

We have heard about certain and impossible events, this video shows how these can be represented using a number.

Which of these events has a probability of 0?

A

It being cloudy tomorrow.

B

The sun not coming up tomorrow.

C

The sun coming up tomorrow.

Worked Solution

Idea summary

If an event has a probability of 0 then the event is imposiible.

If an event has a probability of 1 then the event is certain.

This video shows you how likelihoods can have fractional representation.

Event X has a probability of \dfrac{6}{10}.

a

If event X was placed on the number line, which section would it be placed in?

A

B

Worked Solution

b

What is the chance of event X occurring?

A

Certain

B

Likely

C

Unlikely

Worked Solution

Idea summary

We can use numbers as well as words to describe chance:

Words for chance | Numbers for chance |
---|---|

\text{Impossible} | 0 |

\text{Unlikely} | \dfrac{1}{4} |

\text{Even} | \dfrac{1}{2} |

\text{Likely} | \dfrac{3}{4} |

\text{Certain} | 1 |

List outcomes of chance experiments involving equally likely outcomes and represent probabilities of those outcomes using fractions

Recognise that probabilities range from 0 to 1