The worksheet generator on this page produces 4th grade adding fractions worksheets with real, freshly randomised numbers — 20 of them per sheet by default — plus the answer key a parent or teacher needs to mark it quickly. The version loaded below opens with items in the shape of 1/4 + 2/4 and 4/11 + 4/11; the key lists 3/4 and 8/11 next to their question numbers.
‘New set of problems’ opens the generator in its own tab. There you can change the problem count and turn the answer key on or off. ‘Print or save as PDF’ opens the print dialog — choose Save as PDF in the printer list to keep the file. The sheet fits US Letter and A4, and the answer key prints on its own page.
The instruction 'add the tops, keep the bottoms' is a fine shortcut and a poor explanation. Ask once per sheet why the denominator stays the same.
This sheet uses like denominators from 3 to 12, and answers are given in simplest form so simplification is practised alongside the addition itself, as the item 3/8 + 4/8 on this sheet shows.
Doing this well is what makes unlike denominators tractable later. A child who is fuzzy about 4/11 + 4/11 will find common denominators impossible.
This is the right place to establish what a denominator actually is, because the arithmetic in 2/9 + 3/9 is easy enough that the concept gets the attention.
Teachers usually place 4th grade adding fractions worksheets alongside the fractions strand for grade 4, which is where the skill sits in the majority of US state frameworks.
| # | Problem | Answer | What to check |
|---|---|---|---|
| 1 | 1/4 + 2/4 = | 3/4 | Watch for: leaving the answer unsimplified |
| 2 | 4/11 + 4/11 = | 8/11 | Check: adding the denominators too |
| 3 | 2/9 + 3/9 = | 5/9 | Look at: simplifying halfway |
| 4 | 7/12 + 3/12 = | 5/6 | Ask about: subtracting in the wrong order |
| 5 | 3/8 + 4/8 = | 7/8 | Watch for: writing an improper fraction when a mixed number is expected |
| 6 | 5/7 + 1/7 = | 6/7 | Check: losing the whole-number part |
Here is one worked through. 4/11 + 4/11 gives 8/11. If your child arrives somewhere other than 8/11 on 4/11 + 4/11, look at the working rather than the answer: nearly every wrong result comes from a skipped step, not an unknown fact.
Take the first problem on the sheet as it stands, 1/4 + 2/4. Work 1/4 + 2/4 out on paper rather than in your head the first few times, say each step aloud, and check the result against 3/4 on the key before moving on.
Answers appear next to their question numbers, so a wrong item like 4/11 + 4/11 can be found in the key in a second and re-worked while it is still fresh.
Keys are produced by the same code that produces the questions, so a mismatch between question and answer is not possible on these sheets.
The sheet is laid out to fit one page on both US Letter and A4. Leave the browser scaling at 100% and turn headers and footers off, and the 20 problems land inside the margins on either paper size.
Portrait orientation is what the sheet is designed for. Landscape works but wastes about a third of the paper, so leave the orientation alone unless you have a reason.
Keep the finished 4th grade adding fractions worksheets in date order — the drop in time across ten sheets is the clearest progress report you will get.
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Free printable math worksheets from a working math academy director in Korea. Problems come from our own code, not from a published workbook. Every sheet prints on US Letter or A4 with its answer key. All worksheets · Worksheet generator · Korean site
Last updated: 2026-09-13