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Strawberry Milk

Problem

A strange cult, with a belief that strawberries contain the Elixir of life, have succesfully isolated the gene responsible for producing the flavour in strawberry plants. However, it seems that they have been able to combine this material with bovine DNA to produce a highly infectious virus that affects cattle. Although the virus causes no harm to the cow, it will cause the milk that it produces to be tainted with a strawberry flavour. Once infected there is no cure and all future generations will produce stawberry flavoured milk.

We were able to intercept an encoded message, sent to all members of the cult, regarding a final meeting to discuss the release of the virus. We know that the meeting has been arranged to take place in Athens, Greece. It is imperative that you decode this cipher so that we can uncover the identity of the mysterious leader of this cult and arrange his arrest.

LFI TIVZG OVZWVI, WLMZOW NXILMZOW, RMERGVH ZOO NVNYVIH GL GSV URMZO NVVGRMT RM ZGSVMH, TIVVXV.

Solution

A little analysis of the punctuation should lead us to the suspicion that the message ends with the location of the meeting: ATHENS, GREECE. We also note the coincidence of the number of letters and the double E in GREECE. If this is the case we are dealing with a monoalphabetic substitution code and we could then set about replacing the known letters:

LFI TIVZG OVZWVI, WLMZOW NXILMZOW, RMERGVH ZOO
??R GREAT ?EA?ER, ??NAL? ?C?ONAL?, ?N??TE? A??

NVNYVIH GL GSV URMZO NVVGRMT RM ZGSVMH, TIVVXV.
?E??ERS T? THE ??NA? ?EET?NG ?N ATHENS, GREECE.

After this, it takes little effort to establish the missing letters:

OUR GREAT LEADER, DONALD MCRONALD, INVITES ALL MEMBERS TO THE FINAL MEETING IN ATHENS, GREECE.

Although not based on the Caesar cipher (moving each letter by a fixed amount), the system employed is not based a random translation table. Can you discover the rule?

If you write out a table of known letters:

A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
Z ? ? W V U T S R ? ? O N M L ? ? I H G F E ? ? ? ?

You should be able to understand, XLWV YIVZPVMT.

Problem ID: 10 (Aug 2000)     Difficulty: 1 Star

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