SubtractionGrade 7

Grade 7 Subtracting Rational Numbers

Subtracting rational numbers in grade 7, where subtracting is adding the opposite. Integers, decimals and mixed numbers across twenty problems.

CCSSAligned to Common Core 7.NS.1: Apply and extend previous understandings of addition and subtraction to add and subtract rational numbers, including representing subtraction of a rational number as adding its additive inverse.
20 problemsAnswer key included

Subtract. Remember that subtracting is adding the opposite. Write each answer in simplest form.

  1. 1.8 - 6 =
  2. 2.5.5 - 0.8 =
  3. 3.-2 1/2 - 2 1/2 =
  4. 4.-8 - (-15) =
  5. 5.8.9 - (-6.9) =
  6. 6.-2 3/4 - 2 2/5 =
  7. 7.-14 - 10 =
  8. 8.-3.2 - 3.2 =
  9. 9.1 1/3 - (-1 1/2) =
  10. 10.-5.1 - 8.3 =
  11. 11.-2/3 - 3/4 =
  12. 12.2 - (-13) =
  13. 13.8.3 - 0.4 =
  14. 14.-3/4 - (-3/5) =
  15. 15.17 - 20 =
  16. 16.6.6 - 5.1 =
  17. 17.2 3/5 - 2 1/6 =
  18. 18.7 - 6 =
  19. 19.-2.3 - 0.9 =
  20. 20.-4/5 - (-2 1/3) =

What this worksheet covers

This is a 20-problem sheet — one page to work through, one page of answers to check against. Within that, fourteen of the twenty problems involve a negative quantity, so the answer is not always larger than what went in; several problems use mixed numbers, which have to be handled without dropping the whole-number part. Grade 7, The Number System, Common Core 7.NS.1: that is the exact slot this page fills.

Skills practiced

At this point in the sequence, work in subtraction is really about subtraction as adding the additive inverse. To finish it, a student has to work in fractional units and simplify the result, keep decimal points aligned rather than right-aligning digits out of habit, and track direction as well as magnitude. Watch how the answers are reached, not just whether they land — the method is what carries into grade 8.

How to use this worksheet

Expect this to take twenty minutes or so of genuine attention. At grade 7, work in subtraction rewards care over speed — a student who rushes it will get the arithmetic right and the signs wrong. Print a second copy before writing on the first; a sheet worked twice a week apart tells you far more than a sheet worked once.

One mistake to watch for

Double negatives collapse the wrong way: 5 − (−3) is answered as 2.

The minus signs are being cancelled by appearance rather than by meaning.

Rewrite as 5 + 3 using the additive-inverse rule from 7.NS.1, and check it on a number line. Subtracting a negative moves right, which is why the result grows.

The full guide to teaching subtractionTeaching subtraction from take-away to signed numbers: the grade 1–8 progression, borrowing across zeros, and the six error patterns that stall students.

Related worksheets

Also aligned to 7.NS.1

Other sheets covering 7.NS.1. Same target, different problems, so a student who has seen this page has not seen these.

A step either side

Subtraction either side of grade 7, for stepping the difficulty rather than repeating it.

No sign-up and no paywall — download the subtraction sheet, print it, and the answers for all twenty problems are on the page behind it.

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