The Grey Labyrinth is a collection of puzzles, riddles, mind games, paradoxes and other intellectually challenging diversions. Related topics: puzzle games, logic puzzles, lateral thinking puzzles, philosophy, mind benders, brain teasers, word problems, conundrums, 3d puzzles, spatial reasoning, intelligence tests, mathematical diversions, paradoxes, physics problems, reasoning, math, science.

lexprod · NOT not a title

So here's a puzzle idea that started with amb and I polished it off and came up with examples. Given the large set of math fans here on the GL, I figure they can take it further than us two.

The puzzles are a string of characters that represent a formula using roman numerals, with all operators, equals sign, and parentheses taken out. Your goal is to place them correctly. For example...

XVII turns into X / V = II or 10/5=2

The idea is that these should all have singular and unambiguous answers. However certain answers may have trivial similar solutions, like when XI could be 11 or (10+1), or where .....IX could be ....=9 or .....-1=10, but they seemed pretty much impossible to avoid. Also the later puzzles in this set are much less thoroughly tested for having multiple solutions due to having high possible combinations and me being lazy.

1. XCX
2. IVIVXVI
3. IVVXX
4. VIIIVXV
5. VIIIVLX
6. CLIVCVI
7. LVICIVXI
8. VIXXXIII
9. XIIIIVXVII
And number 10's kind of a bonus....
10. VIIXXLII
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I'll have a P please...

Jack_Ian · Big Endian

I'll start with the easy ones

1. X = C / X
2. IV * IV = XVI
3. IV * V = XX
4. (V - II) * I * V = XV Probably not the intended solution

ralphmerridew · Daedalian Member

Alternate answer to 4: V*II+I*V=XV

Guest* · Guest

Or
4. V * II * I * V / X = V.

Maybe multiplying by I should be disallowed.

Zag · Tired of his old title

5. VIII * V - L = -X Also probably not the intended solution
or just
5. VIII * V = L - X
or
5. V * II * IV = L - X

Guest* · Guest

5. VI * II * V = LX.
6. (C + L) * IV / C = VI.

Zag · Tired of his old title

10. V * II x X = L * II Using one of the X's as a multiplication symbol. Extreme Delectation

or

10 V ^ II * X = X * L / II

Gomez · candid chimera

For 1 you could have X x C = X^3

Sentran · Ray of Sucking Funshine

Possible answer for 7: L*(V+I)/C=-I-V+X-I
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Sentran
"Speaking of double negatives, I haven't read greylab yet today." - Lifeinmomland

Zag · Tired of his old title

or 7: L * VI / C = I / V * X + I

Guest* · Guest

Or 7. (L * (V - I) / C) * I * V / X = I, although again using multiplication by I

Jack_Ian · Big Endian

8. V * IX / X / X * II ≈ I Wink

8. V - IX + X = X / II + I
9. XI - I + II + V = XVII

Jack_Ian · Big Endian

11. LXVIILXXIIIIXCVIIII
(operators allowed: + - * / ^ = )

Zag · Tired of his old title

It seems that there are always going to be too many options when it is that long. I only moved left to right on this one, never going back more than 3 letters once they were placed and only a little peeking ahead.

LX /V /II *L /X -X + II = (II * X + C) / VI + II / I

(checking)
60, 12, 6, 300, 30, 20, 22 = 120, 20, 22, 22

Jack_Ian · Big Endian

I guess brackets aren't technically operators, but the solution shouldn't need them.

lexprod · NOT not a title

These would probably work best if you gave the missing symbols I suppose, say "+ + =" or whatever.
_________________
I'll have a P please...

Jack_Ian · Big Endian

I think that would make it too easy. I did specify that you should only need to add characters from the following list "+-*/^=" in order to get a solution though.

Jack_Ian · Big Endian

Zag · Tired of his old title

LOL. Like we were going to come up with that. If you had hinted about Pythagoras, perhaps.

Amb · Amb the Hitched.

I wondered about doing words as well: eg does a formula for VIVID, CIVIC, MIMIC, or MIX exist. Sadly there arent enough roman-numeral words to make this likely.