In this activity, we will work out a subtraction by counting on using a number line.
Example
Work out 332 - 153 =
We use the number line to count up from the smaller number to the larger number.
First step: go to the next hundred, i.e. 200 here (153 + 47 = 200)
Second step: count up in hundreds to the hundred below your given number, i.e. 300 here (200 + 100 = 300)
Third step: count up to the given number, i.e. 332 here (300 + 32 = 332)
Answer is 47 + 100 + 32 = 179
So, 332 - 153 = 179
These can be quite complicated so we'll take it slowly through some questions.