MS.CC.NF.4. Number and Operations--Fractions
Build fractions from unit fractions by applying and extending previous understandings of operations on whole numbers.
NF.4.3. Understand a fraction a/b with a > 1 as a sum of fractions 1/b.
NF.4.3(a) Understand addition and subtraction of fractions as joining and separating parts referring to the same whole.
NF.4.4. Apply and extend previous understandings of multiplication to multiply a fraction by a whole number.
NF.4.4(a) Understand a fraction a/b as a multiple of 1/b. For example, use a visual fraction model to represent 5/4 as the product 5 x (1/4), recording the conclusion by the equation 5/4 = 5 x (1/4).