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Proof (Posted on 2002-05-29) Difficulty: 3 of 5
Prove that 3.999... = 4

  Submitted by Half-Mad    
Rating: 3.6667 (9 votes)
Solution: (Hide)
3.9999... = X 
3.9999... * 10 = 39.9999.... = 10X 
10X - 3.9999... = 9X 
39.9999... - 3.9999... = 36 = 9X 
36 / 9 = 9X / 9 = 4 
therefore, X = 4 

Comments: ( You must be logged in to post comments.)
  Subject Author Date
SolutionPuzzle Solution: Method 3K Sengupta2022-02-18 23:21:09
EquivalentBractals2007-11-14 16:11:50
SolutionBy CalculusK Sengupta2007-11-14 03:57:50
SolutionA Different MethodK Sengupta2007-03-24 11:48:28
re: doin my part to balance the playing fieldPercy2005-11-15 19:16:32
re: Thoughts of PPercy2005-11-15 18:46:42
Some ThoughtsThoughts of PCeeAnne2005-11-15 13:30:20
re: Illegal Operations - my take on itbrad2005-10-25 23:35:17
re: Illegal OperationsJosh706792005-10-20 17:27:21
Solutiondoin my part to balance the playing fieldJosh706792005-10-20 17:23:01
re: Powl2005-10-17 22:20:00
Hints/TipsPPercy2005-10-17 20:40:08
Illegal OperationsEric2005-08-01 15:22:23
i dont think you got it.nate2005-02-04 02:06:18
re: ...horseshoes and grenadesDan2005-01-07 16:33:10
...horseshoes and grenadesJack Squat2003-12-31 15:12:11
re(3): solution is wrongFederico Kereki2003-11-28 23:45:27
re(3): solution is wrongTristan2003-11-28 14:39:56
re(2): solution is wrongVictor Zapana2003-11-28 08:39:33
re: solution is wrongTristan2003-11-28 00:49:17
re(4): IdeasSilverKnight2003-11-27 12:28:58
solution is wrongVictor Zapana2003-11-27 11:29:41
re(3): IdeasGamer2003-11-27 10:49:48
re: more thoughtsGamer2003-11-27 10:48:28
Some Thoughtsmore thoughtsTristan2003-11-16 15:47:57
re(2): IdeasSilverKnight2003-11-16 13:03:20
re: IdeasTristan2003-11-15 10:29:59
IdeasGamer2003-11-15 07:42:07
re(4): alternate proofSilverKnight2003-10-02 18:28:42
re(3): alternate proofTristan2003-10-02 17:39:00
re(2): alternate proofSilverKnight2003-10-02 13:06:38
re: alternate proofGamer2003-10-02 07:22:12
Solutionalternate proofTristan2003-10-01 21:10:08
re: Problem with 2 SolutionsJim C2003-07-18 05:52:30
Problem with 2 SolutionsGamer2003-04-11 15:14:20
re: heheGamer2003-03-09 14:46:52
heheJames2002-10-26 17:53:46
re: 1 = 0 ???TomM2002-08-24 09:58:46
1 = 0 ???Dulanjana2002-08-24 04:19:32
re:TomM2002-08-01 07:52:42
re:levik2002-07-31 11:15:22
No Subjectbill cochran2002-07-31 09:48:56
re: Then...TomM2002-06-08 12:36:07
Then...Dulanjana2002-06-04 04:53:48
SolutionProofTomM2002-05-30 11:24:12
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