Even and Odd Numbers
Even Numbers
Any integer that can be divided exactly by 2 is an even number.
The last digit is 0, 2, 4, 6 or 8
Example: −24, 0, 6 and 38 are all even numbers
Odd Numbers
Any integer that cannot be divided exactly by 2 is an odd number.
The last digit is 1, 3, 5, 7 or 9
Example: −3, 1, 7 and 35 are all odd numbers
Odd numbers are in between the even numbers.
Adding and Subtracting
When we add (or subtract) odd or even numbers the results are always:
| Operation | Result | Example (red is odd, blue is even) |
|---|---|---|
| Even + Even | Even | 2 + 4 = 6 |
| Even + Odd | Odd | 6 + 3 = 9 |
| Odd + Even | Odd | 5 + 12 = 17 |
| Odd + Odd | Even | 3 + 5 = 8 |
(The same thing happens when we subtract instead of adding.)
Multiplying
When we multiply odd or even numbers the results are always:
| Operation | Result | Example (red is odd, blue is even) |
|---|---|---|
| Even × Even | Even | 4 × 8 = 32 |
| Even × Odd | Even | 4 × 7 = 28 |
| Odd × Even | Even | 5 × 8 = 40 |
| Odd × Odd | Odd | 5 × 7 = 35 |
Odd Fact
Every odd number has an "e" in it!
4818, 4819, 4820, 6173, 6658, 6180, 6181, 6665, 6666, 6667, 6182