Home > College Algebra > Ciphers > Multiplicative Cipher | Decimation Cipher (encoder / decoder) example

21. Multiplicative Cipher | Decimation Cipher example (encoder / decoder) ( Enter your problem )
  1. Examples
Other related methods
  1. A1Z26 Cipher (Letter to number Cipher)
  2. ADFGVX Cipher
  3. ADFGX Cipher
  4. Affine Cipher
  5. Alberti Cipher
  6. Atbash Cipher
  7. Autokey Cipher / Autoclave Cipher
  8. Bacon Cipher
  9. Beaufort Cipher
  10. Bifid Cipher
  11. Caesar Cipher
  12. Chaocipher
  13. Columnar transposition Cipher
  14. Double Transposition Cipher
  15. Enigma machine Cipher
  16. Four Square Cipher
  17. Gronsfeld Cipher
  18. Hill Cipher
  19. Kamasutra Cipher | Vatsyayana Cipher
  20. Morse Code Translator
  21. Multiplicative Cipher | Decimation Cipher
  22. Nihilist Cipher
  23. Playfair Cipher
  24. Polybius Square Cipher
  25. Porta Cipher
  26. Rail fence Cipher
  27. ROT-5 Cipher
  28. ROT-13 Cipher
  29. ROT-18 Cipher
  30. ROT-47 Cipher
  31. ROT-N Cipher
  32. Running Key Cipher
  33. Substitution Cipher
  34. Tap code Cipher | Knock code Cipher
  35. Three Square Cipher
  36. Trifid Cipher
  37. Trithemius Cipher
  38. Two-square Cipher
  39. Vigenere Cipher

20. Morse Code Translator
(Previous method)
22. Nihilist Cipher
(Next method)

1. Examples





1. Multiplicative Cipher encoder

Text : ABCD efghi
Multiplication Key : 3
Alphabet : abcdefghijklmnopqrstuvwxyz


Solution:
A multiplicative cipher encrypts a message by multiplying each letter's numerical value (0-25) by a fixed key (which is coprime to 26) and the corresponding letter is substituted.

Alphabet = abcdefghijklmnopqrstuvwxyz

Letterabcdefghijklmnopqrstuvwxyz
Number012345678910111213141516171819202122232425

Each letter is shifted down based on the key letter
PlaintextABCD efghi
Text Value
(2)
012345678
((2) * 3) Mod 2603691215182124
CiphertextADGJ mpsvy

Plaintext : ABCD efghi
Multiplication Key : 3
Ciphertext : ADGJ mpsvy

2. Multiplicative Cipher encoder

Text : hello world
Multiplication Key : 3
Alphabet : abcdefghijklmnopqrstuvwxyz


Solution:
A multiplicative cipher encrypts a message by multiplying each letter's numerical value (0-25) by a fixed key (which is coprime to 26) and the corresponding letter is substituted.

Alphabet = abcdefghijklmnopqrstuvwxyz

Letterabcdefghijklmnopqrstuvwxyz
Number012345678910111213141516171819202122232425

Each letter is shifted down based on the key letter
Plaintexthello world
Text Value
(2)
74111114221417113
((2) * 3) Mod 26211233=733=742=1666=1442=1651=2533=79
Ciphertextvmhhq oqzhj

Plaintext : hello world
Multiplication Key : 3
Ciphertext : vmhhq oqzhj





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20. Morse Code Translator
(Previous method)
22. Nihilist Cipher
(Next method)





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