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Stage 1

Patterns in subtraction II


Here we will use patterns in subtraction to help us find the difference between a two-digit and single-digit number.

Sometimes, you can partition or split the tens number to help. For example, 16 is the same as one ten and 6 ones.

Let's look at an example, can you see a pattern in the difference sum or the answers?




So, in this example, we can see that when subtracting 9 from a two-digit number ending in six, you get an answer with a number ending in seven.

Worked Examples

question 1

$12-4=8$124=8. Use this to find:

  1. $22-4=\editable{}$224=

  2. $32-4=\editable{}$324=

  3. $42-4=\editable{}$424=

  4. $72-4=\editable{}$724=

question 2

question 3 

Complete the pattern below.

  1. $\editable{}$ $11$11 $\editable{}$ $15$15

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