Fact Families Within 1000 Worksheets for 3rd Grade

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Grade 3MathAddition & SubtractionCCSS 3.NBT.A.2

Skill: Writing related addition and subtraction facts for three-digit numbers within 1000

Preview of the Fact Families Within 1000 printable worksheet
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Teaching tips and what to try next

Designed for third graders who can add and subtract three-digit numbers with regrouping and have met fact families with smaller numbers. Checking only the first addition fact with pencil and paper, then writing the other three from it, saves time and shows how the facts depend on each other. For more column practice, see Mixed 3-Digit Addition and Subtraction; to find a missing part, try Missing Addends Within 1,000.

10 versions, each with its own answer key

Same skill and layout, a fresh set of problems in every version, so children can keep practicing without repeating a page. Problems are not repeated between versions unless a skill has only a small number of possible problems (for example, the addition facts within 10).

Download all 10 versions (one PDF)All 10 answer keys (PDF)

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About this worksheet

Third graders add and subtract fluently within 1000, and fact families are a good way to see how those two operations undo each other. If 248 + 375 = 623, then 623 – 375 and 623 – 248 can be answered from the same three numbers. This third-grade worksheet uses fact family triangles with three-digit numbers.

The page has six triangles. The total is at the top of each triangle, and the two parts are at the bottom corners. Children write two addition facts and two subtraction facts for each family on the four lines below. Both parts are three-digit numbers from 100 to 899, and every total is from 300 to 999. Many of the families need regrouping to check, so the page doubles as practice with careful column work. Each of the ten versions has new families and its own answer key.

How to use it: ask your child to check each family before writing all four facts. Adding the two parts on scrap paper should give the total at the top. That one check makes every other fact in the family correct too. A common mistake is starting a subtraction fact with a part instead of the total. Remind your child that the biggest number, the whole, always comes first in a subtraction fact. For extra practice, cover one corner of a triangle and ask which fact would find it.

The answer key lists all four facts for every family. For two-digit families, try our Fact Families Within 100 worksheet. To practice the column work on its own, try our Mixed 3-Digit Addition and Subtraction worksheet.