Add and Subtract

Now we will consider the four basic operations with whole numbers: addition, subtraction, multiplication, and division.

WholeNumbers

Adding Whole Numbers

Addition means putting things together. The numbers to be added are called the addends. The total is called the sum.  The digits are aligned in columns to ensure that like terms are added. First we add all the numbers in the ones place, then we add all the numbers in the tens place, and so on. Example:

Add

 

 

 

 

You will need to carry a number whenever the sum of the addends is greater than nine. Example:

Carry

 

 

 

 

Usually, we write the numbers in a column format with ones, tens, hundreds, etc. aligned, then add each column beginning with the ones, and carry-over digits to the left.

AlignR

 

 

 

 

 

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Add_Integers

Missing_Addends

 

Subtracting Whole Numbers.

Subtraction means take away (it is opposite of addition). The answer in a subtraction problem is called the difference. Subtrahend is the number to be subtracted from another number (the minuend)            minuend – subtrahend = difference

minus

 

 

 

To find the difference between two numbers, sometimes you need to regroup, or borrow, from another number. Example:

Borrow

 

 

 

 

When the digit in the subtrahend is larger, decompose 1 unit of higher value into 10 units of the next lower value, and regroup.

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Subtract Whole Numbers

Reverse_Subtraction

Add and Subtract Whole Numbers

Solving Equations with Whole Numbers

Solving Equations by Addition or Subtraction

 

Addition and subtraction are opposite operations, so you can use one to check the other.  If A + B = C, then C – B = A

CheckAdd

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Word Problems – Using Whole Numbers 

Word problems vocabulary

Whole Numbers Addition

Whole Numbers Subtraction

Write your own word problem:

Word problem Writing Template

Problem Solving Format