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Monday Madness

12 min read

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Some wooden matches have been arranged on a table to form the following "equation":
[external image: Posted Image]

Can you rearrange the matchsticks, to make the statement true?

(your equation must contain all 10 of the matches).

What is the few number of matches that need to be relocated?
if you move the horizontal match and the match representing one from the left side, and place them vertically on the right you have x1 = 1x11, or "x times one = one times x times one times one" or x = x. True and moving two match sticks.
I think I can make it true moving only one match. But, I'll give someone else a crack at it. I sort of pounced on this one :)
Actually, my official reply is read "x times one = one times x time eleven.

Not good. So, I'm going to whip out my one match move (I think I found two different one match moves):

If you take the match representing "one" on the right-hand side and place it over the "equals" sign, you get

x + 1 does not equal x. True, and a one match move.

your equation must contain all 10 of the matches


According to the Merriam-Webster dictionary… equation is :
  • the act or process of equating
  • a usually formal statement of the equality or equivalence of mathematical or logical expressions

Therefore a statement of inequality could not properly represent an equation. (neither could the spelling of the work TEN, which I think would only use 9 matches)
OK. How about moving the horizontal match in the plus sign to stand vertically next to the "one" on the right side of the equations so that it reads x11 = 11x - true by the commutative property of multiplication (and an expression of equality).

OK. How about moving the horizontal match in the plus sign to stand vertically next to the "one" on the right side of the equations so that it reads x11 = 11x - true by the commutative property of multiplication (and an expression of equality).

Might require a little "shifting" of matches to make room…. so how many total are you going to relocate?
I've come up with two answers for this puzzle, one decent one and one sneaky one. I'll go with the decent one first.

If you think of the matchsticks as representing Roman numerals, you can move one matchstick to get this:

X + I = XI or 10 + 1 = 11, which is a true statement.

And, if there are no mathematicians here who are going to talk about the 'logical biconditional' and take me to task about the exact meanings of mathematical symbols, I may also get away with this sneaky one.

If you again think of the matchsticks as representing Roman numerals, you can move one matchstick and change the equals (=) sign into an equivalence sign (≡) to get this:

X - I ≡ IX or 10 - 1 is equivalent to 9, which is (very nearly) a true statement.

Do I win a cookie, Tomk? [external image: Posted Image] :D
@Achamian, I don't like your "sneaky" answer as I feel that an equivalency is not quite the same as an equality because it is really dealing with defining identities… rather than equality which calls for a solution. Yet, Except for mathematicians, I can see where "equation" is used in that situation. Bottom line… You've come up with a solution to the problem the requires one match to be moved. :thumbup: Anybody else got an answer?

Anybody else got an answer?


Naaaa thought Ten was going to be a crazy one hehehehe

Jimbo1