Mathematics

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50 mins

Teacher/Student led

Learning Goals

Learning Outcomes

Lesson Files

+80 XP

Teacher-led from the board — pupils need no device

What you need:
IWB/Projector/Large Screen

Probability as a Fraction: Out of Total Outcomes

Learn to calculate probability by counting favourable outcomes and total outcomes, then writing the result as a simplified fraction. Work with spinners, dice, and two-dice combinations.

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1 Getting Started
2 Watch and Notice
3 Try It Together
4 Work It as a Fraction in Your Copy
5 Class Challenge
6 What Did We Notice?
7 What's Next
Pupil practice

Your turn

Your teacher is running this lesson on the board. Here is the part you can try yourself.

Your written work is on page 95

Dice roller

Worked example

1 - Getting Started ~4 mins

Here is a wheel split into six equal segments, numbered 1 to 6.

Hands up: what is the chance of the arrow landing on segment 3? Is it a big chance or a small one?

👇 Mark your steps as done as you complete them.

+5 XP

2 - Watch and Notice ~9 mins

The interactive shows a wheel, then a die, then two dice. For each one we name an event and count two things: how many outcomes make it happen, and how many outcomes there are in all. Watch what goes on the bottom of the fraction each time.

👇 Mark your steps as done as you complete them.

+10 XP

3 - Try It Together ~10 mins

We'll work through these two-dice questions on the board. Roll and watch the histogram build. Then, for each one, count the favourable pairs before we write the fraction.

A sum of 2.
A sum of 7.
A sum of 12.
A sum bigger than 10.

Key point

The histogram shows what happened when we rolled. Counting the pairs gives the probability.

Two dice: favourable sums

+15 XP

4 - Work It as a Fraction in Your Copy ~3 mins

COPYBOOK MOMENT

In your maths copy, work each probability as 'favourable / total' and write it as a fraction. Underline your answer, and simplify it where you can.

One segment on a six-segment wheel
An even number on a six-sided die
A prime number on a six-sided die
Two dice adding to 7

+10 XP

5 - Class Challenge ~8 mins

Key point

We'll spin these wheels and write each probability as a fraction. Predict each one before we count.

One segment on a four-segment wheel
An even number on an eight-segment wheel
A number bigger than 6 on the eight-segment wheel
A prime number on the eight-segment wheel (remember, a prime has exactly two factors, itself and 1)

Wheels: probability as a fraction

+15 XP

Pupil practice

Module 7 · Data, Chance and the Co-ordinate Plane Data & Chance

Lesson 101 · Probability as a Fraction: Out of Total Outcomes

Download Activity Book page (PDF)

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