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Cipher Decoding - Intermediate Level: vigenere cipher INTERMEDIATE

Level up your cipher decoding skills with this comprehensive review. 20 intermediate-level problems await in Worksheet 14 of 30. Focus area: vigenere cipher. Learn cipher algorithms, secret codes, military codes through systematic practice. Designed for mid-level learners seeking moderate complexity with mixed patterns.

📝 Worksheet 14 of 30 • 20 questions • ⏱️ Estimated time: 20 minutes • 🎯 Intermediate level

What you'll learn in this worksheet:
Your progress through Cipher Decoding
Worksheet 14 of 30 (46% complete)

Question 1

Using reverse cipher (writing backwards), decode: 'LLABTOOF'
Reverse cipher: LLABTOOF reversed is FOOTBALL
reverse, backwards

Question 2

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

Question 3

If 'FUNGUS' is encoded as 'SHATHF' using Caesar cipher, what is the shift value?
Caesar cipher: FUNGUS → SHATHF. Shift = 13
caesar, shift

Question 4

Using Autokey cipher with initial key 'MYSTERY', encode: 'BROTHER'
Autokey cipher: BROTHER with key 'MYSTERY' → NPGMLVP
autokey, vigenere

Question 5

Using Playfair cipher with keyword 'ALGORITHM', encode: 'MATH'
Playfair with keyword 'ALGORITHM': MATH → IOHM
playfair, digraph

Question 6

If 'TREATMENT' is encoded as 'GERNGZRAG' using Caesar cipher, what is the shift value?
Caesar cipher: TREATMENT → GERNGZRAG. Shift = 13
caesar, shift

Question 7

Using ROT13 cipher, decode: 'RUST'
ROT13 (shift 13): RUST → EHFG
rot13, rotation

Question 8

Using Rail Fence cipher with 5 rails, encode: 'LAKE'
Rail Fence (5 rails): LAKE → LAKE
railfence, transposition

Question 9

Using Rail Fence cipher with 3 rails, encode: 'DOWN'
Rail Fence (3 rails): DOWN → DONW
railfence, transposition

Question 10

Using ROT13 cipher, decode: 'CATALYST'
ROT13 (shift 13): CATALYST → PNGNYLFG
rot13, rotation

Question 11

Using Columnar Transposition cipher with key 'CODE', encode: 'VARIABLE'
Columnar Transposition with key 'CODE': VARIABLE → VARLIEAB
transposition, columnar

Question 12

Decode the Base64 string: 'V09STEQ='
Base64 decoding: V09STEQ= → WORLD
base64, hex, encoding

Question 13

Using the same Caesar cipher that encodes 'NOVEL' as 'UVCLS', decode: 'NYHCPAF'
Shift = 7. NYHCPAF decoded (shift -7) = GRAVITY
caesar, shift

Question 14

Using Playfair cipher with keyword 'PLAYFAIR', encode: 'MOTHER'
Playfair with keyword 'PLAYFAIR': MOTHER → GTQMGI
playfair, digraph

Question 15

In Morse code, what does '.-- .- .-.. -.-' represent?
Morse decoding: WALK → .-- .- .-.. -.-
morse, dots-dashes

Question 16

Using Baconian cipher (5-bit binary encoding), decode: '00110 00000 01011 00000 10111 11000'
Baconian decoding: 00110 00000 01011 00000 10111 11000 → GALAXY
baconian, binary

Question 17

Using keyboard shift cipher (shift right on QWERTY), encode: 'FINANCE'
Keyboard shift (right): FINANCE → GOMSMVR
keyboard, qwerty

Question 18

Using Autokey cipher with initial key 'ENIGMA', encode: 'CIPHER'
Autokey cipher: CIPHER with key 'ENIGMA' → GVXNQR
autokey, vigenere

Question 19

Using Rail Fence cipher with 3 rails, encode: 'NETWORK'
Rail Fence (3 rails): NETWORK → NOEWRTK
railfence, transposition

Question 20

Using book cipher with 'The Quick Brown Fox' [THE, QUICK, BROWN, FOX, JUMPS, OVER, THE...] (5 pages, 9 words), decode positions: (pg1, w7), (pg3, w1), (pg4, w2), (pg4, w7)
Position decoding: THE THE QUICK THE
book, position
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