Subtracting Fractions with the Same Denominator
Subtracting fractions that share the same denominator follows a simple rule — subtract the numerators and keep the denominator unchanged.
What You Need to Know
Key Concept Diagram
Subtract only the numerators when fractions have the same denominator (e.g. 5/6 − 2/6 = 3/6)
The denominator tells you the size of each part and never changes during subtraction
Always simplify the answer if possible (e.g. 3/6 = 1/2)
Fraction subtraction can be modelled on a number line by moving left from the starting fraction
Key Vocabulary
Difference
The result of subtracting one number or fraction from another
Simplify
To write a fraction in its lowest terms by dividing numerator and denominator by their highest common factor
Lowest terms
A fraction where the numerator and denominator share no common factor other than 1
Like fractions
Fractions with the same denominator, making addition and subtraction straightforward
Knowledge Check
Select the correct answer for each question. Click "Check Answer" to see if you are right.
Question 1
What is 7/10 − 3/10?
Question 2
4/10 simplified to its lowest terms is:
Question 3
A jug holds 9/12 of a litre of juice. Sam drinks 4/12 of a litre. How much is left?
Key Concepts Summary
- ●Subtract only the numerators when fractions have the same denominator (e.g. 5/6 − 2/6 = 3/6)
- ●The denominator tells you the size of each part and never changes during subtraction
- ●Always simplify the answer if possible (e.g. 3/6 = 1/2)
- ●Fraction subtraction can be modelled on a number line by moving left from the starting fraction