Adding fractions practice
Adding fractions is easy once the bottom numbers match. Noggli starts with fractions that already match, then moves on to finding a common denominator and adding mixed numbers.
What your child practises
- Year 3add fractions with the same denominator
- Year 4subtract fractions with the same denominator
- Year 5add fractions where one denominator is a multiple of the other
- Year 6add fractions with different denominators
- Year 6add mixed numbers
Mix-ups Noggli looks out for
- Adds the bottom numbers as well as the top numbers when adding fractions
Adding fractions with the same denominator
When the denominators match, add the numerators and keep the denominator the same: 3/8 + 4/8 = 7/8. The bottom number tells you the size of the pieces, and adding does not change the size of the pieces.
Adding fractions with different denominators
Change one or both fractions so they have the same denominator, then add. For 1/3 + 1/5, both can become fifteenths: 5/15 + 3/15 = 8/15. In Year 5 one denominator is a multiple of the other (2/3 + 1/6); in Year 6 neither is, and mixed numbers join in.
Helping at home
- Draw two bars the same length and split them into the pieces. Seeing that eighths and quarters are different sizes makes the rule make sense.
- Practise equivalent fractions first: finding a common denominator is just equivalent fractions in disguise.
- Check the answer is sensible: 1/2 + 1/3 must be more than 1/2 and less than 1.
Made for children who worry about getting it wrong
A clue, not a cross
A wrong answer gets a clue and another go. A second miss shows how it works, step by step.
No clock
Nothing counts down. Confidence first, speed follows on its own.
The right level
After a few questions Noggli knows where your child is, and every question after that adapts.
Related practice
Questions parents ask
How do you add fractions with different denominators?
Find a common denominator, usually by multiplying or using a multiple both denominators share, rewrite each fraction as an equivalent fraction, then add the numerators. 1/3 + 1/5 = 5/15 + 3/15 = 8/15.
Why is 1/3 + 1/5 not 2/8?
Adding the bottom numbers is the most common mistake. The denominator is the size of the pieces, so it does not get added. Noggli includes that wrong answer as an option on purpose, and explains it if your child picks it.
What year do children learn to add fractions?
Adding fractions with the same denominator is in Year 3. Different denominators where one is a multiple of the other is Year 5, and any denominators plus mixed numbers is Year 6.
Practise this every day, at the right level
Noggli works out where your child is in every topic and adjusts each question to suit. Free, with no timers, no scores and no child accounts.