Explain the relationship between modular arithmetic and the

Explain the relationship between modular arithmetic and the Caesar cipher.

Solution

we see that applying the Caesar cipher corresponds just to adding 3 (mod 26). To decipher, we can either subtract 3 modulo 26

for ciphering the plain text we just add 3 to the whole of 26 letters of the alphabet and we get the ciphered code

when we want to decipher it we just subtract 3