Subtract up to 4-digit numbers | Year 5 Mathematics PDF Download

Introduction

Subtraction of numbers can be efficiently done using the column method. This method is particularly useful when subtracting large numbers.

Examples

Example: 1

Let's delve into using the column subtraction method with a 3-digit subtraction example:

• Start from the ones column: 8 - 5 = 3
  
• Proceed to the tens column: 40 - 20 = 20. Write down 2 in the tens column representing 20.
  
• Move to the hundreds column: 500 - 100 = 400. Note down 4 in the hundreds column representing 400.
  
• The finished subtraction - 423

Example: 2

Subtraction of 343 - 237
When subtracting two large numbers using a place value column, if the digit in the second number is larger than the corresponding digit in the first number, direct subtraction isn't possible. In such cases, you need to borrow a digit from the next column.
This example demonstrates how it works:

• Starting from the ones column: 3 - 7
  
• Subtracting 7 from 3 isn't possible, so borrow one ten from the tens column, making it 13 - 7 = 6.
  
• In the tens column, after exchanging a ten, 40 becomes 30, resulting in 30 - 30 = 0.
  
• Subtracting in the hundreds column: 300 - 200 = 100. Representing 100 in the hundreds column.
  
• Combining these results gives the final subtraction: 343 - 237 = 106.

Example: 3

If you can subtract two three-digit numbers, you can apply the same method to subtract two four-digit numbers.
The method remains the same regardless of the number of digits in the numbers.
Consider this example:

• What is 4328 - 1436? Begin with the ones column and subtract the corresponding digits.
  
• Moving on to the tens column, borrow from the hundreds column since you cannot subtract 3 tens from 2 tens. After borrowing, you have 12 tens minus 3 tens.
  
• In the hundreds column, borrow again from the thousands column so that the subtraction becomes 12 hundreds minus 4 hundreds.
  
• Finally, subtract in the thousands column. 3 thousand take away 1 thousand. Then you have your final answer!

Subtraction Techniques and Tips

• Utilize the column method: This method proves particularly useful when subtracting larger numbers. By segregating numbers into their place values, it becomes simpler to execute the subtraction process accurately.
• Place value separation: Ensure numbers are organized based on their respective place values - ones, tens, hundreds, and thousands. This organization facilitates a systematic subtraction process.
• Start from the right: Initiate the subtraction process from the rightmost column (usually the ones column). Proceeding in this manner helps maintain accuracy throughout the computation.
• Estimation and verification: Consider estimating the answer before carrying out the actual subtraction. Post-subtraction, always verify your result to ensure precision. Remember, you can validate your subtraction by performing addition as a check.
• Recognition of keywords: Pay attention to specific words in word problems that indicate subtraction. Words such as "take away," "difference," "less than," and others mentioned earlier are indicative of subtraction operations.