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Five 0s

Five 0s

Posers and Puzzles

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Given five zeroes, using any mathematical operations, can you make a total of 120?

-Ray.

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Originally posted by rgoudie
Given five zeroes, using any mathematical operations, can you make a total of 120?

-Ray.
(0! + 0! + 0! + 0! + 0!)!

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Originally posted by royalchicken
(0! + 0! + 0! + 0! + 0!)!
Excellent!

I love this puzzle.

-Ray.

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Can you please explain how this puzzle works?

How does that total 120?

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Originally posted by skims
Can you please explain how this puzzle works?

How does that total 120?
0! (factorial) is 1. So it's (1+1+1+1+1)! = 5! = 5*4*3*2*1 = 120

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How is 0! equal to 1? Can someone please explain it to me?

Thanks

1 edit
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Originally posted by skims
How is 0! equal to 1? Can someone please explain it to me?

Thanks
It's to make the following equation work. (x!)/(y!)=(x-y)! This works for all numbers. I'll give an example, let's say x,y=3, then it would be (3!)/(3!)=(3-3)! ---> 6/6=0! 1=1 and the equation holds since 0!=1. But if it equalled zero, like you'd expect, then the equation wouldn't work.

It's similar to how x^0=1

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That sounds like a botch job to me. What is the factorial of a negative number?

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Originally posted by nickhawker
That sounds like a botch job to me. What is the factorial of a negative number?
Actually, my equation doesn't work. It must be some different one. I do know that the factorial of 0 is 1 though. I'll let someone with more experience (and memory 😛) take over for me in explaining this.

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0! is one? That's a new one for me.

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Originally posted by Coconut
0! is one? That's a new one for me.
I didn't know that either, but my calculator agrees.

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Originally posted by crazyblue
I didn't know that either, but my calculator agrees.
Yeah, it is. It's just defined that way.

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http://www.themathpage.com/aPreCalc/factorial.htm

3 edits
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This is not the first time this subject has been visited in this forum... there was a thread called 0! in this forum posted on Jun 20, 2004. Right now, it's on page 20 of this forum if you care to take a look...

or, let's see if I can copy the url:

http://www.redhotchess.com/board/showthread.php?threadid=11652

ack, tried to make it a link but dunno the bracket code for it

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Originally posted by Suzianne
This is not the first time this subject has been visited in this forum... there was a thread called 0! in this forum posted on Jun 20, 2004. Right now, it's on page 20 of this forum if you care to take a look...

or, let's see if I can copy the url:

http://www.redhotchess.com/board/showthread.php?threadid=11652

ack, tried to make it a link but dunno the bracket code for it
oooh-i wondered why bowmann had dug up that old thread 😛