Learning Objectives
- Understand what subtraction means
- Subtract small numbers from each other
- Use the minus (โ) sign correctly
- Solve simple subtraction problems with pictures
- Find the difference between two numbers
Key Concepts
What is Subtraction?
Subtraction means taking away some objects from a group. When we subtract, the answer is always smaller than the number we started with. We use the minus sign (โ) to show subtraction. For example, if you have 5 chocolates and eat 2, you have 5 โ 2 = 3 chocolates left.
Subtracting with Objects
We can use real things to subtract. Take 7 stones. Remove 3 stones. Count the stones left. You have 4 stones left. So 7 โ 3 = 4. You can also use your fingers to help you subtract.
Subtraction Facts
Subtracting 0 from any number gives the same number. For example, 8 โ 0 = 8. Subtracting a number from itself gives 0. For example, 5 โ 5 = 0. These facts are important to remember.
Subtraction on a Number Line
On a number line, to subtract, start at the bigger number and jump backwards. If you start at 8 and jump back 3 steps, you land on 5. So 8 โ 3 = 5. Always jump to the left to subtract.
Relation Between Addition and Subtraction
Addition and subtraction are opposites. If 3 + 4 = 7, then 7 โ 4 = 3 and 7 โ 3 = 4. Knowing addition facts helps us do subtraction faster.
Important Terms
- Subtraction: Taking away from a group to find how many are left
- Minus (โ): The sign we use for subtraction
- Difference: The answer we get after subtracting
- Take Away: Another way of saying subtract
- Left Over: What remains after taking away
Quick Revision
- Subtraction means taking away from a group
- The minus sign (โ) tells us to subtract
- Subtracting 0 gives the same number
- Subtracting a number from itself gives 0
- On a number line, we jump backwards to subtract
- Addition and subtraction are related: if 2 + 5 = 7, then 7 โ 5 = 2
- Practice: 9 โ 4 = 5, 6 โ 2 = 4, 8 โ 8 = 0