# Teaching 4.NF.B.3.c – Add and Subtract Mixed Numbers with Like Denominators

## Number & Operations – Fractions – 4th Grade

**Build fractions from unit fractions.**

CCSS.Math.Content.4.NF.B.3.c

Add and subtract mixed numbers with like denominators, e.g., by replacing each mixed number with an equivalent fraction, and/or by using properties of operations and the relationship between addition and subtraction.

**Teacher Notes**

Knowing how do you decompose an improper fraction into a sum of a whole number and a number less than 1 is the first step of understanding a mixed number. You should start with using visual models to build understanding. When adding and subtracting mixed numbers we are joining or separating parts within the same whole.

**Student Knowledge Goals**

I know that mixed numbers can be written as fractions.

I can use the properties of operations to solve addition and subtraction problems involving mixed numbers with like denominators.

I can use what I know about whole number addition and subtraction to solve problems with mixed numbers.

I can use what I know about adding and subtracting fractions to solve problems with mixed numbers.

I know that mixed numbers can be combined or separated (composed and decomposed).

I can use a variety of strategies for adding and subtracting mixed numbers.

I understand that mixed numbers can be combined or separated (composed and decomposed).

**Vocabulary**

improper fraction

mixed number

**Lessons**

Engage NY Module 5 F-29 – Estimate sums and differences using benchmark numbers.

Engage NY Module 5 F-30 - Add a mixed number and a fraction.

Engage NY Module 5 F-31 - Add mixed numbers.

Engage NY Module 5 F-32 - Subtract a fraction from a mixed number.

Engage NY Module 5 F-33 – Subtract a mixed number from a mixed number.

Engage NY Module 5 F-34 - Subtract mixed numbers.

**Student Video Lessons**

Learn Zillion - Add and subtract mixed numbers with like denominators

Virtual Nerd - Understand a fraction a/b with a > 1 as a sum of fractions 1/b

Study Jams - Adding and Subtract mixed numbers

**Online Problems and Assessments**

Khan Academy – Questions and Video Lessons

Add and subtract mixed numbers with like denominators

** Online Games**

Adding Subtracting Mixed Numbers

**Printables**

Fraction Bars

Benchmark Fraction Strips

Adding Subtracting Mixed Numbers

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