Adding Fractions With Like Denominators Worksheets
Free printable adding fractions with like denominators worksheets with answer keys. Add or subtract fractions with the same denominator, such as 3/8 + 4/8.
Using this page
Add or subtract fractions with the same denominator, such as 3/8 + 4/8. Grade 4 in the Common Core treats this as joining or separating parts of the same whole. The answer key gives each answer in simplest form, as a mixed number when it is more than one. Suits around Year 5 in Australia and Grade 4 in the US (Common Core 4.NF.B.3), but use whatever level fits the child.
Tips
- Draw a quick bar or circle when a question feels abstract; pictures make fraction rules make sense.
- Say fractions in words, such as 'three eighths', to keep the size of the parts in mind.
- Simplify answers at the end unless your class does it differently.
- Link fractions to money and time: a quarter of a dollar is 25 cents and a quarter of an hour is 15 minutes.
Worked example
3/8 + 4/8. The parts are all eighths, so add the numerators: 3 + 4 = 7. The answer is 7/8. For 5/6 + 3/6 = 8/6, which is more than one whole: 8/6 = 1 2/6 = 1 1/3.
Common mistakes
Adding the denominators too, so 3/8 + 4/8 becomes 7/16. The size of the parts does not change.
Leaving an answer like 8/6 when the class expects a mixed number in simplest form.
How to use this generator
Choose the options above the sheet: the number of questions and the settings for this kind of worksheet. Every change makes a new sheet straight away, and New worksheet gives a different set of questions with the same settings.
Each sheet has a worksheet number printed at the top. Type the same number later, or keep the page link, to print exactly the same questions and answer key again. Leave Answer key page ticked to print the answers on a second page, then press Print. Every printed page carries the makekite logo and web address.
Common questions
Why does the denominator stay the same?
It names the size of the parts. Adding three eighths and four eighths gives seven eighths, just as three apples and four apples make seven apples.
How are answers written in the key?
Fraction answers are given in simplest form, and answers greater than one are written as mixed numbers, such as 1 1/3.
Can I print the same worksheet again?
Yes. Note the worksheet number printed at the top, or keep the link in your browser's address bar, which ends with that number. Entering it later gives the same questions and answers.
Is it free?
Yes. There is no sign-up, and nothing you choose is sent anywhere: the sheets are made in your browser.