In modular arithmetic, a number is said to be congruent to 0 mod 5 if it can be divided by 5 without leaving a remainder. This means any integer that can be expressed in the form of 5k, where k is also an integer, will be congruent to 0 mod 5. Examples of such numbers include:
- 0 (5 x 0)
- 5 (5 x 1)
- 10 (5 x 2)
- 15 (5 x 3)
- 20 (5 x 4)
- -5 (5 x -1)
- -10 (5 x -2)
Essentially, all multiples of 5, whether positive, negative, or zero, are congruent to 0 mod 5. Understanding congruences is helpful in various fields, including number theory, cryptography, and computer science.