La. Admin. Code tit. 28 § CLXXI-1105

Current through Register Vol. 50, No. 11, November 20, 2024
Section CLXXI-1105 - Number and Operations-Fractions
A. Explain why a fraction a/b is equivalent to a fraction (n x a)/(n x b) by using visual fraction models, with attention to how the number and size of the parts differ even though the two fractions themselves are the same size. Use this principle to recognize and generate equivalent fractions. (Denominators are limited to 2, 3, 4, 5, 6, 8, 10, 12, and 100.)
B. Compare two fractions with different numerators and different denominators, e.g., by creating common denominators or numerators, or by comparing to a benchmark fraction such as 1/2. Recognize that comparisons are valid only when the two fractions refer to the same whole. Record the results of comparisons with symbols [GREATER THAN], =, or [LESS THAN], and justify the conclusions, e.g., by using a visual fraction model. (Denominators are limited to 2, 3, 4, 5, 6, 8, 10, 12, and 100.)
C. Understand a fraction a/b with a 1 as a sum of fractions 1/b. (Denominators are limited to 2, 3, 4, 5, 6, 8, 10, 12, and 100.)
1. Understand addition and subtraction of fractions as joining and separating parts referring to the same whole.

Example: 3/4=1/4 + 1/4 + 1/4

2. 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.

3. 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.
4. Solve word problems involving addition and subtraction of fractions referring to the same whole and having like denominators, e.g., by using visual fraction models and equations to represent the problem.
D. Multiply a fraction by a whole number. (Denominators are limited to 2, 3, 4, 5, 6, 8, 10, 12, and 100.)
1. Understand a fraction a/b as a multiple of 1/b.

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).)

2. Understand a multiple of a/b as a multiple of 1/b, and use this understanding to multiply a fraction by a whole number.

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 x a)/b.)

3. 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.

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?

E. Express a fraction with denominator 10 as an equivalent fraction with denominator 100, and use this technique to add two fractions with respective denominators 10 and 100.

Example: Express 3/10 as 30/100, and add 3/10 + 4/100=34/100.

F. Use decimal notation for fractions with denominators 10 or 100.

Example: Rewrite 0.62 as 62/100; describe a length as 0.62 meters; locate 0.62 on a number line diagram; represent 62/100 of a dollar as $0.62.

G. Compare two decimals to hundredths by reasoning about their size. Recognize that comparisons are valid only when the two decimals refer to the same whole. Record the results of comparisons with the symbols [GREATER THAN], =, or [LESS THAN], and justify the conclusions, e.g., by using a visual model.

La. Admin. Code tit. 28, § CLXXI-1105

Promulgated by the Board of Elementary and Secondary Education, LR 421048 (7/1/2016).
AUTHORITY NOTE: Promulgated in accordance with R.S. 17.6, R.S. 17:24.4, and R.S. 17:154.