In previous lessons, students expressed a fraction as a product of a unit fraction and a whole number . In this lesson, students transition to seeing a fraction as a sum of unit fractions and non-unit fractions with the same denominator. Students see that a fraction with a numerator greater than 1 can be decomposed into sums in different ways. They write equations to record the decomposition (for example, ). Later, they write equations to represent addition of fractions with the same denominator.
Action and Expression
MLR7
Explain (orally) strategies for representing a non-unit fraction as a sum of fractions with the same denominator.
Generate addition expressions that represent decomposing a non-unit fraction.
Reflect on the times you observed students listening to one another’s ideas today in class. What norms would help each student better attend to their classmates' ideas in future lessons?
Standards Alignment
Building On
3.NF.A.1
Understand a fraction as the quantity formed by 1 part when a whole is partitioned into equal parts; understand a fraction as the quantity formed by parts of size .
Decompose a fraction into a sum of fractions with the same denominator in more than one way, recording each decomposition by an equation. Justify decompositions, e.g., by using a visual fraction model. Examples: ; ;