Solve word problems that call for addition of three whole numbers whose sum is less than or equal to 20, e.g., by using objects, drawings, and equations with a symbol for the unknown number to represent the problem.
Standard:
MA.1.AR.1.1
Description:
Apply properties of addition to find a sum of three or more whole numbers.
Standard:
MA.1.AR.2.3
Description:
Determine the unknown whole number in an addition or subtraction equation, relating three whole numbers, with the unknown in any position.
