NumberKey Stage 3

Adding fractions - with the same denominator

Add fractions with the same denominator.

  • Adding fractions with the same denominator means working with equal-sized parts.
  • Add the numerators. Keep the denominator the same.
  • Simplify if needed by factorising and cancelling the highest common factor.

Example 1

Same-sized parts

Calculate.

Add the numerators; keep the denominator.

Example 2

Simplify the result

Work out the result and simplify fully.

Add the numerators; keep the denominator.Highest common factor: 4.Cancel the common factor from top and bottom.

Remember
The denominator describes the size of the parts. Do not add or subtract the denominators.

Your turn

Question 1

Calculate.

Check answer
Add the numerators; keep the denominator.
Question 2

Calculate.

Check answer
Add the numerators; keep the denominator.
Question 3

Calculate. Give your answer in its simplest form.

Check answer
Add the numerators; keep the denominator.Highest common factor: 3.Cancel the common factor from top and bottom.
Question 4

Calculate. Give your answer in its simplest form.

Check answer
Add the numerators; keep the denominator.Highest common factor: 3.Cancel the common factor from top and bottom.
Question 5

Calculate. Give your answer in its simplest form.

Check answer
Add the numerators; keep the denominator.Highest common factor: 4.Cancel the common factor from top and bottom.