Recognise Odd or Even Numbers from a Subtraction

In this activity, we will be carrying out a subtraction and then deciding whether the answer is odd or even.

Example

Is the answer to this odd or even?

81 - 61

Answer

81 - 61 = 20

Numbers that end in the digit 0, 2, 4, 6 or 8 are even.

Numbers that end in the digit 1, 3, 5, 7 or 9 are odd.

20 is even.

Are you happy with that?

You can look back at this page while tackling the questions by clicking on the red help button on the screen.