Understand the meaning of the equal sign, and determine if equations involving addition and subtraction are true or false. e.g., Which of the following equations are true and which are false? 6 = 6, 7 = 8 - 1, 5 + 2 = 2 + 5, 4 + 1 = 5 + 2.

Recognize and generate equivalent fractions, e.g., `sf(1/2)` = `sf(2/4)`; `sf(4/6)` = `sf(2/3)`. Explain why the fractions are equivalent. e.g., using a visual fraction model.

Using concrete models or drawings and strategies based on place value, properties of operations, and/or the relationship between operations:

• add and subtract decimals to hundredths;
• multiply and divide decimals to hundredths.

Relate the strategy to a written method and explain the reasoning used. Notes on and/or: Students should be taught to use concrete models and drawings; as well as strategies based on place value, properties of operations, and the relationship between operations. When solving any problem, students can choose to use a concrete model or a drawing. Their strategy must be based on place value, properties of operations, or the relationship between operations. Note: Division problems are limited to those that allow for the use of concrete models or drawings, strategies based on properties of operations, and/or the relationship between operations (e.g., 0.25 ÷ 0.05). Problems should not be so complex as to require the use of an algorithm (e.g., 0.37 ÷ 0.05).

Compute unit rates associated with ratios of fractions. e.g., If a person walks `sf 1/2` mile in each `sf 1/4` hour, compute the rate as the complex fraction `sf(1/2)/(1/4)` miles per hour, equivalently 2 miles per hour with 2 being the unit rate. Note: Problems may include ratios of lengths, areas, and other quantities measured in like or different units, including across measurement systems.