Two-Digit and One-Digit Subtraction Explained Simply

Understanding Two-Digit and One-Digit Subtraction 🧮

Subtracting a one-digit number from a two-digit number is a fundamental arithmetic skill. Let's break it down with clear examples and explanations.

Basic Concept

Subtraction involves finding the difference between two numbers. When subtracting a one-digit number from a two-digit number, we're essentially taking away a smaller quantity from a larger one.

Method 1: Without Borrowing

If the one-digit number is smaller than the ones digit of the two-digit number, we can subtract directly.

Example:

Subtract 5 from 28.

1. Write the problem:

  28
-  5
----
  

2. Subtract the ones digits: $8 - 5 = 3$.
3. Bring down the tens digit (2).

  28
-  5
----
  23
  

4. So, $28 - 5 = 23$.

Method 2: With Borrowing 🤝

If the one-digit number is larger than the ones digit of the two-digit number, we need to borrow from the tens digit.

Example:

Subtract 7 from 32.

1. Write the problem:

  32
-  7
----
  

2. Since 2 is smaller than 7, we need to borrow 1 from the tens digit (3). This reduces the tens digit by 1 (3 becomes 2), and adds 10 to the ones digit (2 becomes 12).

  2 12
-  3 2
-   7
----
  

3. Subtract the ones digits: $12 - 7 = 5$.
4. Bring down the tens digit (2).

  2 12
-  3 2
-   7
----
  2 5
  

5. So, $32 - 7 = 25$.

Practice Problems ✍️

• $45 - 3 = ?$
• $61 - 8 = ?$
• $73 - 6 = ?$

Key Takeaways 🚀

• When subtracting, always start with the ones digits.
• If you can't subtract directly, borrow from the tens digit.
• Practice regularly to improve your skills!