Chance and Probability

Students learn how to write a probability as a simplified fraction.  As learning progresses they use equivalent fractions to compare probabilities and predict outcomes by finding a fraction of an amount.

This unit takes place in Term 5 of Year 7 and is followed by probability, outcomes and Venn Diagrams in Year 8.

Chance and Probability Lessons
Prerequisite Knowledge
  • Compare and order fractions, including fractions > 1
  • Use common factors to simplify fractions; use common multiples to express fractions in the same denomination
  • Add and subtract fractions with different denominators and mixed numbers, using the concept of equivalent fractions
Key Concepts
  • The terms outcome, event and probability are key to describing the likelihood of an event occurring
    • Outcome is the result of an experiment
    • An event is a set of outcomes of a probability experiment
    • Probability describes the likelihood of an event occurring.  A probability can be given as fraction, decimal or percentage.
  • An event which is impossible has a  probability of zero.  An event which is certain to occur has a probability of one.
  • When listing all the permutations of two or more events students need a logical and exhaustive systematic method.
  • When working with experimental data a probability can only be estimated as contextual factors are likely to have been a factor in the outcome.
Working mathematically

Develop fluency

  • Use language and properties precisely to analyse numbers, algebraic expressions, 2-D and 3-D shapes, probability and statistics.

Reason mathematically

  • Explore what can and cannot be inferred in statistical and probabilistic settings, and begin to express their arguments formally.

Solve problems

  • Select appropriate concepts, methods and techniques to apply to unfamiliar and non-routine problems.
  • Begin to model situations mathematically and express the results using a range of formal mathematical representations
Subject Content


  • Record, describe and analyse the frequency of outcomes of simple probability experiments involving randomness, fairness, equally and unequally likely outcomes, using appropriate language and the 0-1 probability scale.
  • Understand that the probabilities of all possible outcomes sum to 1
  • Generate theoretical sample spaces for single and combined events with equally likely, mutually exclusive outcomes and use these to calculate theoretical probabilities.

Leave a Reply

Your email address will not be published. Required fields are marked *

You may use these HTML tags and attributes:

<a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <s> <strike> <strong>

This site uses Akismet to reduce spam. Learn how your comment data is processed.

Mr Mathematics Blog

Teaching in a Bubble

Practical tips and advice for preparing to teach in year group bubbles.

Problem Solving – Perimeter and Area

Students are challenged to apply the rules of arithmetic to a series of real-life, functional problems.

Behaviour Management in a Mathematics Lesson

As we approach the start of the next term I thought I would share some tips on behaviour management in a mathematics lesson. These are things that I have picked up over the years and have worked well for me. I am sure there are opposing viewpoints and you may find some of these tips […]