Subtraction patterns over increasing place values

Key notes:

🔹 Key Idea
  • In subtraction, we often see patterns when numbers increase by place values (ones, tens, hundreds, thousands).
  • Each time we move to the next place value, the difference between numbers changes in a pattern.
🔹 Step-by-Step Explanation
Subtracting with Ones
  • Example:
    10 – 1 = 9
    20 – 1 = 19
    30 – 1 = 29
    👉 The difference increases by 10 each time as the tens place grows.
Subtracting with Tens
  • Example:
    100 – 10 = 90
    200 – 10 = 190
    300 – 10 = 290
    👉 The difference increases by 100 each time as the hundreds place grows.
Subtracting with Hundreds
  • Example:
    1,000 – 100 = 900
    2,000 – 100 = 1,900
    3,000 – 100 = 2,900
    👉 The difference increases by 1,000 each time as the thousands place grows.
Subtracting Same Number Patterns
  • Example:
    555 – 111 = 444
    666 – 222 = 444
    777 – 333 = 444
    👉 Pattern: The difference remains the same when both numbers increase equally.
🔹 General Patterns
  • If the subtrahend stays the same → the difference increases by the value of the place added.
  • If both numbers increase equally → the difference stays the same.
🔹 Practice Examples
  • 50 – 5 = ?
    60 – 5 = ?
    70 – 5 = ?
    👉 What pattern do you see?
  • 400 – 40 = ?
    500 – 40 = ?
    600 – 40 = ?
    👉 What happens as the numbers increase?
  • 900 – 300 = ?
    1,000 – 400 = ?
    1,100 – 500 = ?
🔹 Quick Tips
  • Look at place values (ones, tens, hundreds, thousands).
  • Check if both numbers increase equally or only one number increases.
  • Identify the pattern in the difference.
✅ Conclusion:


Subtraction patterns help us see how numbers change when place values grow. This makes subtraction faster and easier to understand.

Learn with an example

🎯 Complete the pattern:

9 − ____ = 5
90 − ____ = 50
900 − ____ = 500
9,000 − ____ = 5,000

Find the first missing number:

9 ones − 4 ones = 5 ones
9 − 4 = 5

Now complete the pattern:

9 tens − 4 tens = 5 tens
90 − 40 = 50

9 hundreds − 4 hundreds = 5 hundreds
900 − 400 = 500

9 thousands − 4 thousands = 5 thousands
9,000 − 4,000 = 5,000

🎯 Complete the pattern:

____− 5 = 4
____− 50 = 40
____− 500 = 400
____− 5,000 = 4,000

Find the first missing number:

9 ones − 5 ones = 4 ones
9 − 5 = 4

Now complete the pattern:

9 tens − 5 tens = 4 tens
90 − 50 = 40

9 hundreds − 5 hundreds = 4 hundreds
900 − 500 = 400

9 thousands − 5 thousands = 4 thousands
9,000 − 5,000 = 4,000

🔥Complete the pattern:

____ – 6 = 3

____ – 60 = 30

____ – 600 = 300

____ – 6,000 = 3,000

Find the first missing number:

9 ones − 6 ones = 3 ones
9 − 6 = 3

Now complete the pattern:

9 tens − 6 tens = 3 tens
90 − 60 = 30

9 hundreds − 6 hundreds = 3 hundreds
900 − 600 = 300

9 thousands − 6 thousands = 3 thousands
9,000 − 6,000 = 3,000

Let’s practice!