Properties of Addition Day 1 Properties Today you are going to learn three properties of addition. Properties of addition are rules that you follow when you add. 1) Zero Property of Addition: When you solve these 4 problems, you use the zero property of addition. 7+0=7 0+99=99 56+0=56 12+0=12 When you add zero to a number, the sum is that number. Please write the Zero Property of Addition in your notes. 1.) Zero Property of Addition: When you add zero to a number, the sum is that number. Examples: 0+19= 19 2,567+0= 2,567 2) Commutative Property of Addition: When you 7+5=12 solve these problems, you use the 34+99 Commutative Property of Addition. 100+27 = 127 5+7=12 = 99+34 27 +100=127 When you change the order of the addends the sum stays the same. Please write the Commutative Property of Addition in your notes. 2.) Commutative Property of Addition: When you change the order of the addends, the sum stays the same. Example: 5+7=12 7+5=12 Practice: Which property is being used to solve these problems? Zero Property of Addition 0 + 7 = 7 ________________________ Commutative Property of Addition 7 + 9 = 9 + 7 ______________________ Commutative Property of Addition 12+99=99+12 ______________________ Zero Property of Addition 0 + 5,012,456= 5,012,456 _____________ 3) Associative Property of Addition: When you solve this problem, you use the Associative Property of Addition. *Remember: Add the numbers in the parentheses FIRST. 12 + (2 + 5) = (12 + 2) + 5 12 + 19 7 = 14 +5 19 When you change the way addends are grouped, the sum stays the same. The associative property helps with mental math. Use the associative property to solve these problems mentally. 146 75 + 25 + 46 = __________________ *Which two numbers did you add first? Why? 521 92 + 421 + 8 = __________________ *Which two numbers did you add first? Why? 845 422 +345 + 78 = __________________ *Which two numbers did you add first? Why? Please write the Associative Property of Addition in your notes. 3.) Associative Property of Addition: When you change the way the addends are grouped, the sum stays the same. Example: (3+7)+10 = 20 3 + (7+10) = 20 Practice: Which property is being used to solve these problems? Zero Property of Addition 0 + 29 = 29 ________________________ Commutative Property of Addition 17 + 19 = 19 + 17 ______________________ Associative Property of Addition 12+(99+3) = 12 + (99+3) ______________________ 6 + (7 + 19) + 8 = (6 +7) + 19 + 8 Associative Property of Addition _____________________ Homework Complete Homework worksheet 3.1