When denominators match, just add or subtract the numerators — the denominator stays the same!
Adding and subtracting fractions is straightforward when the denominators are the same. The denominator tells us the SIZE of each piece — and size does not change when we combine or remove pieces. We just count the pieces (numerators).
Like denominators → add (or subtract) numerators only. The denominator stays unchanged.
A pizza is cut into 8 equal slices. You eat 3/8 and your friend eats 2/8. Together you ate: 3/8 + 2/8 = 5/8 of the pizza.
A ribbon is 7/10 m long. You cut off 3/10 m. Remaining ribbon: 7/10 − 3/10 = 4/10 m (which simplifies to 2/5 m).
When the result is an improper fraction, convert to a mixed number:
Remember This!
Always simplify your answer if possible! 4/10 = 2/5 because both 4 and 10 share a common factor of 2. Divide numerator and denominator by 2.
What is 5/8 + 6/8?