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How to decrypt the following cipher text using frequency analysis?

GBSXUCGSZQGKGSQPKQKGLSKASPCGBGBKGUKGCEUKUZKGGBSQEICACGK

GCEUERWKLKUPKQQGCIICUAEUVSHqKGCEUPCGBCGQOEVSHUNSUGKUZCG

QSNLSHEHIEEDCUOGEPKHZGBSNKCUGSUKUASERLSKASCUGBSLKACRCACU

ZSSZEUSBEXHKRGSHWKLKUSQSKCHQTXKZHEUQBKZAENNSUASZFENFCUOC

UEKBXGBSWKLKUSQSKNFKQQKZEHGEGBSXUCGSZQGKGSQKUZBCQAEIISKO

XSZSICVSHSZGEGBSQSAHSGKHMERQGKGSKREHNKIHSLIMGEKHSASUGKNSH

CAKUNSQQKOSPBCISGBCqHSLIMQGKGSZGBKGCGQSSNSZXQSISQQGEAEUGC

UXSGBSSJCqGCUOZCLIENKGCAUSOEGCKGCEUqCGAEUGKCUSZUEGBHSKGEH

BCUGERPKHEHKHNSZKGGKAD

4 Answers

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  • 2 months ago

    Ignoring the fact that this is not a question about Chemistry,

    the count of encrypted letters goes like this:

    S = 61

    G = 57

    K = 52

    U = 38

    C = 38

    E = 35

    Q = 26

    H = 23

    B = 20

    Z = 19

    A = 17

    I = 13

    N = 13

    L = 10

    X = 8

    P = 7

    R = 7

    O = 7

    q = 4

    F = 3

    M = 3

    W = 3

    V = 3

    D = 2

    T = 1

    J = 1

    Supposing the plain text language to be English (which is a crucial assumption) the first two letters ought to stand for "e" and "t".  After that, it's fairly clear that the first word is "the".  Then just looking at what there is already decrypted and using the frequency tables, one can work out the whole plain text:

    theunitedstateswasatpeacewiththatnationandatthesolicita

    tionofjapanwasstillinconversationwithitsgovernmentandit

    semperorlookingtowardthemaintenanceofpeaceinthepacificin

    deedonehourafterjapaneseairsquadronshadcommencedbombingi

    noahuthejapaneseambassadortotheunitedstatesandhiscolleag

    uedeliveredtothesecretaryofstateaformalreplytoarecentamer

    icanmessagewhilethisreplystatedthatitseemeduselesstoconti

    nuetheexistingdiplomaticnegotiationsitcontainednothreator

    hintofwarorarmedattack

    The only unusual parts are:

    1) The plain text "o" is out of order from the usual frequency counts in English of "etoainshrdlu".  The rest of the letters follow the list of frequencies remarkably well --

    more so than I'd expect in such a short text.

    2) The encrypted "Q" and "q" are both "s" in plain text.  Adding the count of "q" to the count of "Q" would not change the position of "Q" in the frequency count, so I don't see why "q" was used.

    [Congratulations on typing such gibberish accurately.]

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  • david
    Lv 7
    2 months ago

    This is related to the Wheel Of Fortune.   They mostly use certain letters because those letter are the most frequently used letters in the English language .. I an not good at that show because I don't know which letters are used most often.  'E' is the most used vowel .. RSTLN are the most used consonants.  Count All the letters in the encrypted text  ... whatever is there most probably represents 'E'  ... the 2nd most in the encryption is probably 'S' or 'R' or T or N ... try sub. those and see if the message looks like words  then go from there.   ====  But I am not count G's etc and do the sub for you.  Good luck.

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  • 2 months ago

    I would say so! B)

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  • 2 months ago

    Try assigning the most used letter in the english alphabet to the most used letter in the cipher, and so on.

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