Description
Learn how to count choices in stages using multiplication.
In Lesson 2 of Counting & Combinatorics, learners discover the multiplication principle: when a process happens in stages, the number of possibilities can often be found by multiplying the number of choices available at each stage.
The lesson develops this idea through outfits, ice creams, game characters, codes, café orders and coloured-ball problems. Learners also explore what happens when earlier choices reduce the number of later options, and when separate cases should be added rather than multiplied.
Included
- Lesson Handout — guided examples, practice, learning prompts and the Mystery Balls challenge.
- Exercises — extra problems on multi-stage counting, no repetition, separate cases and working backwards from a total.
- Answers and discussion at the back of both resources.
Topics include:
- the multiplication principle;
- two-stage and multi-stage choices;
- counting codes;
- choices without repetition;
- multiplying through stages;
- adding separate cases;
- factor problems and working backwards.
The materials are designed for a parent and child to explore together or for an older learner to work through independently.
This is the printable companion to Lesson 2: Choices in stages in the free Sumthing Else Counting & Combinatorics course.
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