The probability that an event will occur is the proportion of times the event is expected to happen in a suitably large experiment.

The frequency is the number of times an event occurs; or the number of individuals (people, animals etc.) with some specific property.

Checking and securing calculating probabilities from tables

Maths

In this unit, pupils use their knowledge of calculating theoretical probabilities and extend this understanding to calculating conditional probabilities using all of the representations encountered in the prior unit.

Conditional probability

Students were asked whether they walked to school or used other transport methods, and how long their journey took them. Find the probability a student had a journey of over 15 minutes.

A spinner with outcomes {1, 2, 3, 5, 9, 15} is spun twice. The outcome of each spin is added together.
Find P(multiple of 10).

A spinner with outcomes {1, 2, 3, 5, 9, 15} is spun twice. The outcome of each spin is added together.
Find P(not a prime number).

People at a bus station were surveyed their age and where their destination was.
Match each frequency from the table to its value.

People at a bus station were surveyed their age and where their destination was.
A person is chosen at random. 
Find P(60 or over and going to Rowanwood).

People at a bus station were surveyed their age and where their destination was.
A person going to Oakfield is chosen at random. 
Find P(under 60).

Here are three decks of cards.
A single card from each of Deck 1, Deck 2, and Deck 3 is drawn to make a trio.
What is the probability that this trio of cards contains a square number?

Sam plays a video game that can either be won or lost.
The probability that Sam wins the video game is 0.42.
The probability that Sam loses the video game is {{}}.

This table shows the mutually exclusive and exhaustive set of outcomes, and the probability of each outcome, from spinning a spinner once.
The value of $$x$$ is {{ }}.


Which of these statements are correct for this frequency tree?

Each card on a deck of 7 cards has a unique integer written on it. A = {factors of 6}, B = {numbers ≥ 6}.
What positive integer could be on the seventh card for events A and B to not be exhaustive?

A game can either be won by either Alex, Sam, or Jacob.
P(Sam wins) = {{ }}.

Starter Quiz