Simple Formulae
This topic covers 4 learning steps, guiding your child from the basics through to confident problem-solving. Each step includes a worked example and adaptive practice questions.
What Your Child Will Learn
- Read a Formula
Understand what a formula means - Area Formula
Use Area = length x width - Perimeter Formula
Use P = 2(l + w) - Mixed Formulae
Choose and apply the correct formula
Common Mistakes
- Confusing an expression with a formula (not understanding that a formula always has an equals sign and describes a relationship)
An expression is a calculation without an equals sign (like 3x + 2). A formula has an equals sign and shows how to calculate something (like A = l × w). A formula tells you "this is how to find something." - Not being able to write a formula from a word problem (struggling to translate English into algebra)
Break it down step by step. "The cost is £5 per person plus a £10 booking fee." Cost = 5 × number of people + 10, or C = 5n + 10. Practise turning sentences into algebra.
Tips for Parents
- Use formulas your child already knows: "Perimeter = 2(l + w). If l = 8 and w = 3, what is the perimeter?" They are already familiar with substitution into formulas.
- Create real-life formulas together: "A taxi charges £3 plus £2 per mile. Write a formula for the total cost." C = 2m + 3.
- Ask your child to write a formula for pocket money: "You get £5 per week plus £1 per chore. Write a formula." P = 5 + c (where c = number of chores).
- Test formulas with different values: "If the formula is C = 3n + 5, what is C when n = 1? When n = 4? When n = 10?"
Key Words
- Formula — A rule written using letters and numbers that shows how to calculate something — like A = l × w.
- Subject — The letter on its own on one side of the formula — in A = l × w, the subject is A.
- Variable — A letter representing a quantity that can change.
- Constant — A fixed number in a formula — in C = 3n + 5, the constants are 3 and 5.
- Derive — Work out or create a formula from information given in words or a pattern.
Where This Fits
Before this topic: Children should understand substitution, know BODMAS, and be comfortable writing expressions with letters.
After this topic: Simple formulae lead to rearranging formulas, deriving formulas from patterns, and using formulas across maths and science in secondary school.
How MathCraft Teaches This
In MathCraft, Simple Formulae is taught through the Geometry & Shape adventure track. Your child follows guided lessons with friendly characters, works through examples step by step, then practises with questions that adapt to their level.
The adaptive engine tracks mastery across all 4 steps, revisiting concepts your child finds tricky and advancing when they're ready. Parents can see detailed progress in the Parent Dashboard.
Practise Simple Formulae with MathCraft
Step-by-step lessons, worked examples, and adaptive practice — all wrapped in an adventure game your child will love.
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