Apply and extend previous understandings of multiplication to multiply a fraction by a whole number. Understand a fraction a/b as a multiple of 1/b (e.g., use a visual fraction model to represent 5/4 as the product 5 × (1/4), recording the conclusion by the equation 5/4 = 5 × (1/4)). Understand a multiple of 𝑎/𝑏 as a multiple of 1/𝑏, and use this understanding to multiply a fraction by a whole number (e.g., use a visual fraction model to express 3 × (2/5) as 6 × (1/5)), recognizing this product as 6/5. (In general, 𝑛 × (𝑎/𝑏) = (𝑛 × 𝑎)/b)). Solve word problems involving multiplication of a fraction by a whole number (e.g., by using visual fraction models and equations to represent the problem).
Number and Operations—Fractions
Build fractions from unit fractions by applying and extending previous understanding of operations of whole numbers.