Even Numbers (Integers)
A number (integer) is even if it is divisible by 2.
Example 1. Determine whether 10 is an even number.
10 is even because $$$\frac{{10}}{{2}}=5$$$ and 5 is an integer number.
Another example.
Example 2. Determine whether 15 is even.
15 is odd, because $$${15}={2}\cdot{7}+{1}$$$ and remainder is not 0.
Now, do a couple of exercises.
Exercise 1. Determine whether 35 is an even number.
35 is not divisible by 2, because $$${35}={2}\cdot{17}+{1}$$$ and remainder is not 0.
So, it is not an even number.
Another exercise.
Exercise 2. Determine whether 100 is even.
100 is even because $$$\frac{{100}}{{2}}={50}$$$ and 50 is an integer number.