Math Is Fun Forum

  Discussion about math, puzzles, games and fun.   Useful symbols: ÷ × ½ √ ∞ ≠ ≤ ≥ ≈ ⇒ ± ∈ Δ θ ∴ ∑ ∫ • π ƒ -¹ ² ³ °

You are not logged in.

#1 Re: This is Cool » The Game of life » 2010-02-07 05:17:25

Thank you bobbym for replying.  I was all set to leave this alone after your post, but a co-worker (we'll call him:  Mr. Coffee) got himself involved.  He believes that there is a problem in the step where we subtract x from each side of the equation.  The way he puts it is:  when you do something to one side of the equation, then you must do it to the other.  So when we substitute 0.99... in for x on the right side of the equation, we must also substitute 0.99... for x on the other side of the equation.  this gives us:

x = 0.99...
10x = 9.99...
10x - x = 9.99... - x
10(0.99...) - 0.99... = 9.99... - 0.99...
9 = 9

could someone look at this and tell me if it's correct, please.   I'm anxious to know if Mr. Coffee has hit upon something, or not. 
thanks.

#2 Re: This is Cool » The Game of life » 2010-02-05 04:43:18

help disproving 1=0.999....

ok, so this has been driving me nuts since I first saw it on the site.  I understand that the mathmatical difference between 1 and 0.999.... is so minute as to make them practically the same thing, but they are not exactly the same.  I can see the math is screwed up . . . well, it's more that I feel it, but I can't seem to disprove this yet.  can anyone help?

#3 Re: Dark Discussions at Cafe Infinity » Purpose of life???? » 2010-01-25 04:41:04

Curly: You know what the secret of life is?
Mitch: No, what?
Curly: This.
Mitch: Your finger?
Curly: One thing. Just one thing. You stick to that and everything else don't mean doodoo.
Mitch: That's great, but what's the one thing?
Curly: That's what you've got to figure out.




It may come from a silly movie that I only half remember, but it's a quote that I'll never forget for the length of my life.  I even wrote a paper for college centered around it.

#4 Re: Dark Discussions at Cafe Infinity » Finally, NASA relents » 2010-01-25 04:30:39

25 in 2012 . . . dang I feel old.  tongue

Anyways.  It's good to know we've finally found some form of life out there.  Now if we could only find evidence of intelligent life.

#5 Re: Dark Discussions at Cafe Infinity » Rant for the day: Trend or random? » 2010-01-25 02:21:45

1.  I agree with this as well.  When your motivated (and if you're not, then you likely wouldn't be doing it on your own time) learning is much easier.

2. I don't really agree with this.  There have always been good teachers, and bad teachers.  Everyone just tends to hear about the bad/angry/dysfunctional teachers more often is all.  (and, hey, that's news/media for you)
At the same time, I hear about my nephew's teachers, and see how they make him more interested in school and learning, and I know there are still good teachers out there.

3. Again, I agree with this.  At least where I am, I've noticed that much of the school work seems severly outdated.  (not to say it's completely useless, just outdated)

4.  please.  There will always be people that take pride in everything that they do.  There will be those that don't care about anything. And the rest of us will fall at varying places in between.  Personally, I've not seen a decline in people taking pride in their jobs, and what they do. Possibly more people dissatisfied with their jobs, but that doesn't stop you from taking pride in doing the job well.

#6 Re: This is Cool » The Game of life » 2010-01-24 08:07:15

In regards to the second link, that actually works anytime you use .999....
for example:

N = 2.99...
(multiply both sides by 10)
10N = 29.99...
(subtract N from both sides)
9N = 27
(divide both sides by 9)
N = 3 = 2.99...


or

N = 0.7999...
(multiply both sides by 10)
10N = 7.999...
(subtract N from both sides)
9N = 7.2
(divide both sides by 9)
N = 0.8 = 0.7999...

#7 Re: Dark Discussions at Cafe Infinity » Try this personality test. » 2010-01-22 08:31:59

Hhmmm,

INFJ

Introverted - 56
Intuitive - 25
Feeling - 50
Judging - 11

Not really sure what that says about me, but hey, there it is.

#8 Introductions » Hey'ya all » 2010-01-18 03:17:33

thoughtdotcom
Replies: 1

Hello everyone, a co-worker indroduced me to this site (he knows how much I like puzzles and math), and I wanted to tell everyone how much I enjoy this site:  I really like the site!  It's awesome!  You people are great!

That being said, I think I'll go check out some more of the puzzles posted smile

Board footer

Powered by FluxBB