The MajorSystem is the most commonly used set of mnemonics. This custom MajorSystem will help you memorize lists of up to 100 items, as well as credit card PINs, phone numbers, and the other numeric trivia of daily life.
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Freeform discussion of this hack goes here.
One of the suggestions in Mind Performance Hacks is that it might be possible to use the system from the MemorizeNumbersWithCarrollsCouplets? hack to create peg words instead of the equivalents supplied with the Major System. The difficulty with this will show up in numbers involving 4 (Q and F) and 8 (H and K). For 48 the possibilities are limited to "Q*H", "F*H", "Q*K", and "F*K" where "*" is any vowel or combination of vowels. Without using "Q*CK" and "F*CK", which could be confused with possibilities involving 3, it's hard to think of suitable nouns. "QUAKE" is one possibility.
84 is almost as bad. While there may be words of the form "K*F" they are not common words. It might be possible to use "HALF", but because Carroll uses C, S, and K for different digits it's not possible to make the rule that it's the sound rather than the spelling that determines how the word should be converted. For 44, "QUAFF" doesn't quite work because the F is doubled. It might be possible to decide that in peg words containing more than two consonants the third and following should be dropped, which would take care of the difficulty, but might cause problems if you also use the system in other ways.
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