# South Carolina - Grade 1 - Math - Algebraic Thinking and Operations - Adding Three Whole Numbers - 1.ATO.2

### Description

Solve real-world/story problems that include three whole number addends whose sum is less than or equal to 20.

• State - South Carolina
• Standard ID - 1.ATO.2
• Subjects - Math Common Core

### Keywords

• Math
• Algebraic Thinking and Operations

## More South Carolina Topics

Understand that the two digits of a two-digit number represent amounts of tens and ones. Understand the following as special cases: A. 10 can be thought of as a bundle of ten ones — called a “ten.” B. The numbers from 11 to 19 are composed of a ten and one, two, three, four, five, six, seven, eight, or nine ones. C. The numbers 10, 20, 30, 40, 50, 60, 70, 80, 90 refer to one, two, three, four, five, six, seven, eight, or nine tens (and 0 ones).

Use nonstandard physical models to show the length of an object as the number of same size units of length with no gaps or overlaps.

1.ATO.7 Understand the meaning of the equal sign as a relationship between two quantities (sameness) and determine if equations involving addition and subtraction are true.

1.ATO.8 Determine the missing number in addition and subtraction equations within 20.

Partition two-dimensional shapes (i.e., square, rectangle, circle) into two or four equal parts.

Apply Commutative and Associative Properties of Addition to find the sum (through 20) of two or three addends.