Page 421 - Math Smart - 7

CHAPTER 18.1

In this chapter
bability Pupils should be able to:

• use the language of
\ 'FBr
probability to describe
What are your chances? and interpret results
involving likelihood and
chance
• understand and use the
probability scale from
Oto 1
If you do not buy a ticket, If you enter a raffle where If you enter a raffle where
• find probabilities
you have NO CHANCE of there are only two tickets, there are many tickets, based on equally likely
winning a prize in the you have a 50/50 chance you are UNLIKELY to win outcomes in simple
raffle. of winning a prize. a prize. contexts

Using likelihood and chance
^ RECALL
to describe probability

Describe the likelihood of
each of these events as
Q hink and Share certain, impossible, likely,

Tom goes to the store to buy cereal. There are four different types of unlikely or equally likely.
a) Getting a tail when
cereal for him to choose from. tossing a coin

/ / / b) Choosing a King from
a deck of cards
m c) Rolling an even number
d) Having one Wednesday
Cereal A Cereal B Cereal C Cereal D
in this week
There are four possible outcomes for this event.
Tom has no preference for the type of cereal, and picks one at random.
What is the probability that he will pick cereal A?

An outcome is the final result of an activity, action or experiment. Tom has to
choose 1 cereal out of 4 different types of cereal. The chance of Tom picking
cereal A is 1 out of 4. |

Probability is the chance or likelihood that something will happen.

Probability is about how likely something is to happen.
When you think about how likely or unlikely something is to happen, you will use
probability terminology such as impossible, unlikely, equally likely, likely or certain.

Some things will never happen.
If you threw an ordinary die, you will never roll a zero.
It is impossible.
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