This study notes covers Worked Example 7: Age Problem within Simplifying Expressions for GCSE Mathematics. Revise Simplifying Expressions in Algebra for GCSE Mathematics with 11 exam-style questions and 5 flashcards. Use this page as part of a wider topic revision path rather than treating it as an isolated fact. It is section 17 of 19 in this topic. Use this study notes to connect the idea to the wider topic before moving on to questions and flashcards.
Worked Example 7: Age Problem
Sarah is x years old. Tom is 3 years older. Their combined age is 27. Form and solve an equation to find Sarah's age.
Step 1 Write expressions
Sarah's age = x
Tom's age = x + 3
Step 2 Form equation
Combined age = 27
x + (x + 3) = 27
Step 3 Solve
2x + 3 = 27
2x = 24
x = 12
Sarah is 12 years old
Practice questions for Simplifying Expressions
Which two terms are like terms?
Explain why 3x + 2x² cannot be simplified to 5x³.