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Cipher Decoding - Intermediate Level: shift ciphers INTERMEDIATE

Comprehensive weakness targeting worksheet covering 20 intermediate-level cipher decoding problems. Worksheet 18 of 30 emphasizes shift ciphers. Master substitution ciphers, transposition ciphers, key-based decoding through detailed explanations. Difficulty: moderate complexity with mixed patterns. Tailored for mid-level preparation.

📝 Worksheet 18 of 30 • 20 questions • ⏱️ Estimated time: 20 minutes • 🎯 Intermediate level

What you'll learn in this worksheet:
Your progress through Cipher Decoding
Worksheet 18 of 30 (60% complete)

Question 1

Using the same Caesar cipher that encodes 'VILLAIN' as 'CPSSHPU', decode: 'DYLZASPUN'
Shift = 7. DYLZASPUN decoded (shift -7) = WRESTLING
caesar, shift

Question 2

Using the same Caesar cipher that encodes 'DANCE' as 'OLYNP', decode: 'CL'
Shift = 11. CL decoded (shift -11) = RA
caesar, shift

Question 3

Using Hill cipher with key matrix [[3, 2], [5, 7]], encode: 'JUSTICE'
Hill cipher: JUSTICE → MYOPCCGZ
hill, matrix

Question 4

Using date-based cipher with date 09-03-2023 (sum of day+month+year = 7), decode: 'MYLLKVT'
Date-based cipher: Shift = 7, MYLLKVT decoded → FREEDOM
date, calendar

Question 5

Using Atbash cipher (A↔Z, B↔Y, C↔X...), decode: 'DOCKER'
Atbash: DOCKER → WLXPVI
atbash, mirror

Question 6

Using date-based cipher with date 12-11-2016 (sum of day+month+year = 11), decode: 'NZXPE'
Date-based cipher: Shift = 11, NZXPE decoded → COMET
date, calendar

Question 7

Using date-based cipher with date 19-06-2024 (sum of day+month+year = 21), decode: 'YVOZ'
Date-based cipher: Shift = 21, YVOZ decoded → DATE
date, calendar

Question 8

Using Vigenère cipher with keyword 'GRAY', encode: 'HELLO'
Vigenère: HELLO with key 'GRAY' → NVLJU
vigenere, polyalphabetic

Question 9

Using ROT13 cipher, decode: 'ANCIENT'
ROT13 (shift 13): ANCIENT → NAPVRAG
rot13, rotation

Question 10

Decode the hexadecimal string: '44454352595054494F4E'
Hex decoding: 44454352595054494F4E → DECRYPTION
base64, hex, encoding

Question 11

Using book cipher with 'Elementary My Dear Watson' [ELEMENTARY, MY, DEAR, WATSON, SHERLOCK, HOLMES, BAKER...] (4 pages, 10 words), decode positions: (pg4, w4), (pg4, w9), (pg2, w10), (pg2, w8)
Position decoding: WATSON MYSTERY CLUE STREET
book, position

Question 12

Using Vigenère cipher with keyword 'GALAXY', decode the ciphertext: 'MAXE'
Vigenère: With key 'GALAXY', MAXE → GAME
vigenere, polyalphabetic

Question 13

Using Baconian cipher (5-bit binary encoding), decode: '10010 01000 10010 10011 00100 10001'
Baconian decoding: 10010 01000 10010 10011 00100 10001 → SISTER
baconian, binary

Question 14

Using date-based cipher with date 06-07-2019 (sum of day+month+year = 4), decode: 'GIPIFVEXMSR'
Date-based cipher: Shift = 4, GIPIFVEXMSR decoded → CELEBRATION
date, calendar

Question 15

Using Hill cipher with key matrix [[7, 8], [11, 13]], encode: 'INTEGRAL'
Hill cipher: INTEGRAL → EXJBWBKN
hill, matrix

Question 16

Using Vigenère cipher with keyword 'JAVASCRIPT', decode the ciphertext: 'OIQE'
Vigenère: With key 'JAVASCRIPT', OIQE → FIVE
vigenere, polyalphabetic

Question 17

Using Playfair cipher with keyword 'LOCK', encode: 'METEOR'
Playfair with keyword 'LOCK': METEOR → SMSFDW
playfair, digraph

Question 18

Decode the hexadecimal string: '4F5045524154494E47'
Hex decoding: 4F5045524154494E47 → OPERATING
base64, hex, encoding

Question 19

Using reverse cipher (writing backwards), decode: 'RECCOS'
Reverse cipher: RECCOS reversed is SOCCER
reverse, backwards

Question 20

Using book cipher with 'To Be Or Not To Be' [TO, BE, OR, NOT, TO, BE, THAT...] (3 pages, 10 words), decode positions: (pg2, w3), (pg1, w7), (pg3, w8)
Position decoding: OR THAT IS
book, position
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