ADDITION PROPERTIESWe add numbers together when we want a TOTAL number. We often add groups of people or objects together to find out how many there are together. The total number we get is called the SUM. The numbers that are added together when we get a sum are called the ADDENDS.
What is the IDENTITY PROPERTY OF ADDITION?
- This is when you have a sum that is the same number as one number in the addition sentence (the other number being added is a zero).
EX: 0 + 6 = 6
32 + 0 = 32
4 + 0 = 4
What is the COMMUTATIVE PROPERTY OF ADDITION?
- This is when you find the same numbers being added together, but in a different order, AND have the same sum.
EX: 4 + 3 = 7 AND 3 + 4 = 7
8 + 9 = 9 + 8
17 = 17
What is the IDENTITY PROPERTY OF ADDITION?
- This is when you have a sum that is the same number as one number in the addition sentence (the other number being added is a zero).
EX: 0 + 6 = 6
32 + 0 = 32
4 + 0 = 4
What is the COMMUTATIVE PROPERTY OF ADDITION?
- This is when you find the same numbers being added together, but in a different order, AND have the same sum.
EX: 4 + 3 = 7 AND 3 + 4 = 7
8 + 9 = 9 + 8
17 = 17
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Let's review! The video below will review our first lesson.
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ROUNDING (Lesson 1.2)We use rounding to tell ABOUT how much or ABOUT how many of something. To round, you are going to look for an easier number to count by that is closest to the number you have. Easier numbers to count by are like 10, 20, 30, 40 or 100, 200, 300.
For example: If I have 289 pencils, I might would tell someone I have ABOUT 290 pencils or I could even tell them that I have ABOUT 300 pencils. Both numbers are closest to the actual number of pencils I have. I would not say that I have about 200 pencils, since my total number of pencils is closer to 300.
When we round numbers, we are giving an estimate. View the videos below to better your understanding of ROUNDING. :-)
For example: If I have 289 pencils, I might would tell someone I have ABOUT 290 pencils or I could even tell them that I have ABOUT 300 pencils. Both numbers are closest to the actual number of pencils I have. I would not say that I have about 200 pencils, since my total number of pencils is closer to 300.
When we round numbers, we are giving an estimate. View the videos below to better your understanding of ROUNDING. :-)
SUBTRACTION