# Puzzle #3

Puzzle #3 is back to the basics.  Once again I’m asking people to reevaluate how they look at numbers.  I provide a step in the right direction by writing out the numbers in English off the bat.  Looking forward to seeing who can solve this one! I received a few answers to Puzzle #2, but none matched what I was looking for.  To add some clarity, I added a pretty big hint and another two equations that demonstrate the core principle.  I’ll post the answer after I get at least one correct response.

Good luck with Puzzle #3.  This weekend I’ll be launching a separate page tracking the weekly riddles, and it will also detail the prizes for correct responses.

Congrats to Jon C. for solving the puzzle.  He provided a detailed solution in the comments, but here is the short version:

Solution

The answer is 4. The function strips the word down to only the letters used in Roman numerals, and the remaining numerals are the result. So f(sIX) = f(IX) = 9. In this case, f(eIghtyseVen) = f(IV) = 4.

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#### 1 Comment

1. The answer is 4. The solution is based on Roman numerals. In each case, the word in parentheses has all letters that aren’t Roman numerals ignored, and the number formed in Roman numerals is converted to Arabic numerals on the right of the equal sign. Thus, ELEVEN is LV is 55, TEN and FOUR contain no Roman numerals so the answer is 0, NINE and EIGHT evaluate to I is 1, SEVEN is V is 5, SIX is IX is 9, and FIVE is IV is 4. EIGHTYSEVEN evaluates to IV, which is 4.