Understand a multiple of `a/b` as a multiple of `sf(1)/b`, and use this understanding to multiply a fraction by a whole number. For example, use a visual fraction model to express 3 x (`2/5`) as 6 x (`1/5`), recognizing this product as (`6/5`). (In general, n x (`a/b`) = `((n · a))/b`.

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: `3/8` = `1/8` + `1/8` + `1/8`; `3/8` = `1/8` + `2/8`; 2 `1/8` = 1 + 1 + `1/8` = `8/8` + `8/8` + `1/8`.

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`).

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. For example, if each person at a party will eat `3/8` of a pound of roast beef, and there will be 5 people at the party, how many pounds of roast beef will be needed? Between what two whole numbers does your answer lie?

An angle that turns through n one-degree angles is said to have an angle measure of n degrees.

An angle is measured with reference to a circle with its center at the common endpoint of the rays, by considering the fraction of the circular arc between the points where the two rays intersect the circle. An angle that turns through `1/360` of a circle is called a "one-degree angle," and can be used to measure angles.

Understand addition and subtraction of fractions as joining and separating parts referring to the same whole.