## Move one stick

A forum for good logic/math puzzles.

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SirGabriel
Posts: 35
Joined: Wed Jul 16, 2014 11:54 pm UTC

### Move one stick

I've seen this puzzle a lot lately:

Move just one match to fix the equation!

Finding one or two solutions is easy, but how about finding all of them? How many different ways can you move just one match to make a true statement?

SirGabriel
Posts: 35
Joined: Wed Jul 16, 2014 11:54 pm UTC

### Re: Move one stick

I've come up with 13 solutions so far.
Spoiler:
8 - 4 = 4
5 + 4 = 9
0 + 4 = 4
5 + 4 ≠ 4
6 - 4 ≠ 4
6 + 4 > 4
5 + 4 ≥ 4
6 - 4 ≤ 4
6 ≠ 4 - 4
6 ≮ 4 - 4
5 ≮ 4 = 4
6 > 4 = 4
5 ≠ 4 = 4

thunk
Posts: 407
Joined: Sat Apr 23, 2016 3:29 am UTC
Location: Arguably Exiled

### Re: Move one stick

Spoiler:
Move the center bar of the middle 4 to make a 9 on the right. You are left with three matches in the middle--6+3=9.
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HonoreDB
Posts: 158
Joined: Tue Feb 06, 2007 4:32 pm UTC
Contact:

### Re: Move one stick

Spoiler:
You get at least one more if you allow bitwise operations:
6 | 4 ≠ 4

SirGabriel
Posts: 35
Joined: Wed Jul 16, 2014 11:54 pm UTC

### Re: Move one stick

HonoreDB wrote:
Spoiler:
You get at least one more if you allow bitwise operations:
6 | 4 ≠ 4

I don't know what that means.

HonoreDB
Posts: 158
Joined: Tue Feb 06, 2007 4:32 pm UTC
Contact:

### Re: Move one stick

SirGabriel wrote:
HonoreDB wrote:
Spoiler:
You get at least one more if you allow bitwise operations:
6 | 4 ≠ 4

I don't know what that means.

Spoiler:
A Bitwise OR is an operator in programming, usually written as "|" in languages that have it. It essentially means: Write both values in base 2, then replace every 0 in one number with the corresponding digit of the other number. 6 is 110, while 4 is 10, so 6 | 4 is 6 (4 doesn't provide any 1s that aren't already in 6). It's normally used along with other bitwise operators like AND (&) to allow a number to compactly represent a bunch of different yes-or-no questions.