Subtraction

What Is Subtraction?

• Subtraction is the process of taking away some things from a group.
• When we subtract, we are finding out how many are left over.
• The answer we get at the end of a subtraction problem is called the Difference.

The Magic Symbols In subtraction, we use two very important signs:

• The Minus Sign (-): This tells us to take a number away.
• The Equal Sign (=): This tells us what is left.
• Example: (We say: "Five minus two equals three").

How to Subtract Numbers Here are three easy ways to find the difference:

1. The "Cross Out" Method

• Draw the first number of items (like 6 cookies).
• Cross out the number you want to take away (cross out 2).
• Count how many cookies are still there. The answer is 4!

2. The "Count Back" Method

• Keep the bigger number in your head.
• Put the smaller number on your fingers.
• Count backward from the number in your head.
• Example for : Keep 7 in your head, put 3 fingers up. Say "7... then count back 6, 5, 4."

3. The Number Line Method

• Start at the first number on the number line.
• Take "jumps" backward (to the left) for the second number.
• The number you land on is your answer.

Special Subtraction Rules

• The Zero Rule: If you subtract 0 from a number, the number stays the same! (Example: ).
• The Same Number Rule: If you subtract a number from itself, the answer is always 0. (Example: ).
• The Order Rule: Unlike addition, you cannot swap the numbers. is not the same as !

Lesson Summary

• Subtraction means taking away from a group.
• We use the - sign to subtract and the = sign for the total left.
• The answer is called the Difference.