Mathematical oddities

jozsefkoma · Post by **jozsefkoma** » Sun Dec 19, 2010 4:09 pm

I posted exactly this post on 3.studio forum but I want show this to other users from this forum

Just look!

13837 * xy * 73=xyxyxyxy
xy is a number between 10 and 99

Example:

13837 *35 * 73=35353535 (35 35 35 35)

Test it on any calculator.
It's work.
Try with another numbers.

Another one:

1 x 8 + 1 = 9
12 x 8 + 2 = 98
123 x 8 + 3 = 987
1234 x 8 + 4 = 9876
12345 x 8 + 5 = 98765
123456 x 8 + 6 = 987654
1234567 x 8 + 7 = 9876543
12345678 x 8 + 8 = 98765432
123456789 x 8 + 9 = 987654321

1 x 9 + 2 = 11
12 x 9 + 3 = 111
123 x 9 + 4 = 1111
1234 x 9 + 5 = 11111
12345 x 9 + 6 = 111111
123456 x 9 + 7 = 1111111
1234567 x 9 + 8 = 11111111
12345678 x 9 + 9 = 111111111
123456789 x 9 +10 = 1111111111

9 x 9 + 7 = 88
98 x 9 + 6 = 888
987 x 9 + 5 = 8888
9876 x 9 + 4 = 88888
98765 x 9 + 3 = 888888
987654 x 9 + 2 = 8888888
9876543 x 9 + 1 = 88888888
98765432 x 9 + 0 = 888888888

1 x 1 = 1
11 x 11 = 121
111 x 111 = 12321
1111 x 1111 = 1234321
11111 x 11111 = 123454321
111111 x 111111 = 12345654321
1111111 x 1111111 = 1234567654321
11111111 x 11111111=123456787654321
111111111 x 111111111 = 12345678987654321

Technos72 · Post by **Technos72** » Sun Dec 19, 2010 4:12 pm

That's real interesting

. I like math. Can't wait for it next semester at school!

StinkerSquad01 · Post by **StinkerSquad01** » Sun Dec 19, 2010 4:57 pm

xyzxyz/7/11/13=xyz
It works with any 3-digit number repeted once.

boywhoflies · Post by **boywhoflies** » Sun Dec 19, 2010 7:05 pm

WOW thats cool!

ben-09 · Post by **ben-09** » Sun Dec 19, 2010 8:48 pm

Thats some interesting maths.

~xpr'd~ · Post by **~xpr'd~** » Sun Dec 19, 2010 11:32 pm

Awesome.
Unneeded poll though. Seriously, there's way too many.

MyNameIsKooky · Post by **MyNameIsKooky** » Sun Dec 19, 2010 11:45 pm

~xpr'd~ wrote:Awesome.
Unneeded poll though. Seriously, there's way too many.

Too many? Like, only 1/8 of the topics in this area are polls.

Qloof234 · Post by **Qloof234** » Sun Dec 19, 2010 11:56 pm

MyNameIsKooky wrote:
~xpr'd~ wrote:Awesome.
Unneeded poll though. Seriously, there's way too many.
Too many? Like, only 1/8 of the topics in this area are polls.

The point is, there shouldn't be that many, let alone threads with polls where they aren't needed.

boywhoflies · Post by **boywhoflies** » Mon Dec 20, 2010 12:01 am

I counted them.It's 36 of the over 100 topics(I can't see that ammout, no other pages are loading

).

MyNameIsKooky · Post by **MyNameIsKooky** » Mon Dec 20, 2010 12:04 am

It's not as popular now.

boywhoflies · Post by **boywhoflies** » Mon Dec 20, 2010 12:08 am

Sorry for DP!
It loaded now, but I needed to close my broswer and re-open it.Anyway, it's 197 topics, and according to my computers calculaor, thats about 71%.

Guppy Star · Post by **Guppy Star** » Mon Dec 20, 2010 10:18 am

You found them or made it yourself?

jozsefkoma · Post by **jozsefkoma** » Mon Dec 20, 2010 1:14 pm

I found it.

Guppy Star · Post by **Guppy Star** » Tue Dec 21, 2010 9:56 am

jozsefkoma wrote:I found it.

Found it? Where?

jozsefkoma · Post by **jozsefkoma** » Tue Dec 21, 2010 10:33 am

On Internet!

I used google.

Blast!10 · Post by **Blast!10** » Tue Dec 21, 2010 3:51 pm

I found something very similar in fourth-grade science class:

x / 9 = 0.xxxxxxxx...
xy / 99 = 0.xyxyxyxy...
xyz / 999 = 0.xyzxyzxyz...
xyzt / 9999 = 0.xyztxyzt...
and so on.

tyteen4a03 · Post by **tyteen4a03** » Tue Dec 21, 2010 4:16 pm

This one's very interesting indeed. Pic taken from Wikipedia.

jozsefkoma · Post by **jozsefkoma** » Tue Dec 21, 2010 4:33 pm

Wow! That is really cool!
0,999...= 1 ???
I think that 0,999...≈1,but 0,999...= 1?
Is amazing!

Marinus · Post by **Marinus** » Tue Dec 21, 2010 4:59 pm

Yes, we spent an entire topic on it.

http://www.pcpuzzle.com/forum/viewtopic.php?t=17109

StinkerSquad01 · Post by **StinkerSquad01** » Tue Dec 21, 2010 5:13 pm

Uh....wait what

StinkerSquad01 · Post by **StinkerSquad01** » Tue Dec 21, 2010 5:13 pm

Uh....wait what

StinkerSquad01 · Post by **StinkerSquad01** » Tue Dec 21, 2010 5:20 pm

Darn dp glitch!_
So, 0.99999999 equals 1?
But it's not possible, because they're two completely different numbers.

Marinus · Post by **Marinus** » Tue Dec 21, 2010 6:54 pm

No, you didn't read well. You forgot the dots ..... after the nines which mean that the nines are repeated infinitely. 0,999999 is not 1, but 0,999999... however is!

jozsefkoma · Post by **jozsefkoma** » Tue Dec 21, 2010 7:53 pm

At my country if a number has period instead of 0,999... we write 0,(9).

jozsefkoma · Post by **jozsefkoma** » Tue Dec 21, 2010 7:54 pm

Sorry for previous post.
I can't edit it.
Instead of "At my country" I wanted to write "In my country"

StinkerSquad01 · Post by **StinkerSquad01** » Tue Dec 21, 2010 10:54 pm

Marinus wrote:No, you didn't read well. You forgot the dots ..... after the nines which mean that the nines are repeated infinitely. 0,999999 is not 1, but 0,999999... however is!

I used a _ to try and make a repeat sign. Something popped into my head,
If 8 ninths is 0.888...(right?)
Then 9 ninths would be 0.999...
but 9 over nine is 1!

Marinus · Post by **Marinus** » Wed Dec 22, 2010 12:45 am

I'm not quite sure what you mean. Do you mean that you understand that 0,99999..... = 1 ?

Qloof234 · Post by **Qloof234** » Wed Dec 22, 2010 12:48 am

Here's how it works:

0.999... = x, our variable.

If you multiply x by 10, you get 9.999...

Taking x away from 10x is taking 0.999... away from 9.999... this gives us 9, which is the same as 9x.

Therefore, x = 1 = 0.999...

Marinus · Post by **Marinus** » Wed Dec 22, 2010 12:54 am

Yes, that's about the same as what Muzo said 2 years ago.

Guppy Star · Post by **Guppy Star** » Wed Dec 22, 2010 9:56 am

If a line 1 is perpendicular to line 2, line 1 is infinitely long. If a 3rd line is drawn somewhere from the line 2 to meet line 1 what will be the angle at which line 3 is drawn?

A: 90 degrees (Competitive studies point of view)