Don't Subtract, Add!

Don’t Subtract Add!

The don’t subtract add technique is used for large subtraction
questions. It is when you turn the number around and
count up to the bigger number e.g.

479 - 357 = ?

You flip the number around so the bigger
number is at the end and then you count from
the smaller number up to the bigger number e.g.

357 + Mystery Number = 479

And the mystery number is the answer

An easy way to count up to the bigger number is by first
counting up to the first clean number e.g.

357 + 3 = 360

Then up to the next and so on

360 + 40 = 400

400 + 70 = 470

470 + 9 = 479

And in the end you add up all the numbers in the middle

3 + 40 = 43

43 + 70 = 113

113 + 9 = 122

And so the answer is 122

I hope you all learned something from this DLO.