Skill: Recognize even and odd numbers

A whole number is even if it can be divided into 2 equal groups with no leftovers. It is odd if dividing by 2 leaves 1 leftover.

A quick way to tell is to look at the ones digit:

• Even: $0, 2, 4, 6, 8$
• Odd: $1, 3, 5, 7, 9$

Example: Is $246$ even or odd?

1. Find the ones digit.
   The ones digit in $246$ is $6$.

2. Check the list.
   $6$ is one of the even digits: $0, 2, 4, 6, 8$.

3. Conclude.
   Therefore, $\boxed{246\text{ is even}}$.

We can check by dividing:

$$246 \div 2 = 123$$

There is no remainder, so $246$ is even. Remember, $0$ is also an even number because $0 \div 2$ leaves a remainder of $0$.