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ganeshie8

  • one year ago

How is this possible \[\frac{1}{4}-\frac{3}{8} = \frac{1}{2}\]

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  1. Astrophysics
    • one year ago
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    It's not :o

  2. CLOBBER02
    • one year ago
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    help me

  3. ganeshie8
    • one year ago
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    just found an awesome reasoning for how that is possible from one of our users xD

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  4. Astrophysics
    • one year ago
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    Haha, that's great :))

  5. random231
    • one year ago
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    rofl xD

  6. random231
    • one year ago
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    wow youre a patient helper ganeshie ;)

  7. UnkleRhaukus
    • one year ago
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    \[\frac14-\frac38\\ =^? \frac{1-3}{4-8}\\ = \frac24\\ =\frac12\\ \]

  8. ganeshie8
    • one year ago
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    Haha was just thrilled by how that user came up with such cute reasoning!

  9. Astrophysics
    • one year ago
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    These kids on here are really smart, they just need the right push :P

  10. UnkleRhaukus
    • one year ago
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    |dw:1433833984854:dw|

  11. Astrophysics
    • one year ago
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    Sorcery!

  12. ganeshie8
    • one year ago
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    thats my fav one! wrong reasoning, right answer they are called happy fractions or something...

  13. Astrophysics
    • one year ago
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    https://www.youtube.com/watch?v=Yajonhixy4g

  14. Astrophysics
    • one year ago
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    And http://mathoverflow.net/questions/94742/examples-of-interesting-false-proofs

  15. ganeshie8
    • one year ago
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    interesting, im still a bit clueless about identifying the flaw in that proof(youtube link) showing all triangles are equilateral ...

  16. ParthKohli
    • one year ago
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    Haha, nice solution. How do you solve this though?

  17. UsukiDoll
    • one year ago
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    I got -1/8 on this T_T!

  18. ParthKohli
    • one year ago
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    Wolfram says the answer is \(-1/8\). How did it get to that figure?

  19. geekfromthefutur
    • one year ago
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    Without wolfram math i wouldn't be smart about math lol

  20. UsukiDoll
    • one year ago
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    lcd yo!

  21. ParthKohli
    • one year ago
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    What...?

  22. UsukiDoll
    • one year ago
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    \[\frac{2}{2} \times \frac{1}{4} - \frac{3}{8} \rightarrow \frac{2}{8} - \frac{3}{8} \rightarrow = -\frac{1}{8}\]

  23. UsukiDoll
    • one year ago
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    find the least common denominator on this... the sign was missing when I saw that reasoning

  24. ParthKohli
    • one year ago
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    Oh wow! Interesting method. Nice.

  25. UsukiDoll
    • one year ago
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    actually that's common x.x anyone out there can use least common denominator

  26. ParthKohli
    • one year ago
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    No I can't.

  27. UsukiDoll
    • one year ago
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    and by the way a - sign was dropped in that image....when clobber did the arithmetic 2-3 = -1 for the numerator

  28. UsukiDoll
    • one year ago
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    but he drew a 1 instead of a -1

  29. ParthKohli
    • one year ago
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    I just believed that these problems were supposed to be solved by Wolfram because they're hard, so I always plugged these numbers into Wolfram. Didn't know people could actually solve these.

  30. geekfromthefutur
    • one year ago
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    Well you can it just takes a while longer to solve the problem but all that matters that getting it solved. Because not every problem is going to be easy as 2 + 2

  31. UsukiDoll
    • one year ago
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    what the...*bangs head*

  32. ParthKohli
    • one year ago
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    Anyway, thank you for sharing this method! More people should know about it. I'm about to finish high-school and my classmates also use Wolfram for solving fractions.

  33. ganeshie8
    • one year ago
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    lol honestly i never found a satisfying explanation for why common denominator is needed when adding/subing fractions

  34. UsukiDoll
    • one year ago
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    O__________________________O! Okay, that's fine for checking answers, but students shouldn't be dependent on it. My university doesn't allow calculators or computers. Have fun with that

  35. Astrophysics
    • one year ago
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    I don't think any mathematics department does ;)

  36. UsukiDoll
    • one year ago
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    wolfram shouldn't be abused... and sometimes even Mr.Wolfy himself makes mistakes

  37. geekfromthefutur
    • one year ago
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    Yea it cant solve every problem.

  38. UsukiDoll
    • one year ago
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    there was a professor who allowed everything ... book, calculator...tablet...but he retired recently

  39. ParthKohli
    • one year ago
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    Haha, ganeshie, it should make sense though. You can add 1/8th and 4/8th of a cake like that, but you can't add 1/8th and half of a cake.

  40. ParthKohli
    • one year ago
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    I will have to revise my fractions after finishing calculus.

  41. UsukiDoll
    • one year ago
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    oh lol @UnkleRhaukus you just broke a math rule with your example.

  42. Astrophysics
    • one year ago
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    Oh I thought you were joking the whole time parth

  43. ParthKohli
    • one year ago
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    ;)

  44. UnkleRhaukus
    • one year ago
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    all triangles are equilateral

  45. ParthKohli
    • one year ago
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    You hoped I was joking the whole time. :P

  46. ParthKohli
    • one year ago
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    I guess I stretched it way too far.

  47. ganeshie8
    • one year ago
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    nope it is fine, the joke is obvious to everyone ;p

  48. Miracrown
    • one year ago
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    I knew it

  49. Astrophysics
    • one year ago
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    http://puu.sh/i9pL3/b1f88e3e47.png

  50. Miracrown
    • one year ago
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    LOL

  51. ganeshie8
    • one year ago
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    should msg it to one of his gfs lol

  52. UsukiDoll
    • one year ago
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    omg dan.

  53. Miracrown
    • one year ago
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    ikr @ganeshie8 ;)

  54. Astrophysics
    • one year ago
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    Anyways check out those false proofs from that link, pretty cool :)

  55. ParthKohli
    • one year ago
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    From comments: The mistake lies in the drawing. The lines are too sloppy and if you actually draw it out, you will see C* always lies on the other side of C (or B* on the other side of B), so subtracting C*C from AC does not make the conclusion valid anymore.

  56. ParthKohli
    • one year ago
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    ``` one of his gfs lol ``` Subtle, I like it.

  57. UsukiDoll
    • one year ago
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    last semester I accidentally typed "Dan I love you" instead of "Dan I need your help" because I was working on a matlab code. T_T! I had to type to two people on os that it wasn't spam and it was an accident.

  58. Astrophysics
    • one year ago
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    http://puu.sh/i9ruW/6515fd86d6.png

  59. ParthKohli
    • one year ago
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    Don't worry, Dan's a player. He just gets everyone to fall in love with him.

  60. UsukiDoll
    • one year ago
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    This was before I had glasses, so yeah...I couldn't see well with small text

  61. geekfromthefutur
    • one year ago
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    Lol. and i wonder who else hes with xD

  62. ParthKohli
    • one year ago
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    @Astrophysics Holy crap, hahaha.

  63. Miracrown
    • one year ago
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    I like it how this post has completely gone off topic

  64. Astrophysics
    • one year ago
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    Sorry haha

  65. ParthKohli
    • one year ago
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    To be fair, the topic isn't something eye-catching.

  66. Miracrown
    • one year ago
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    All good @Astrophysics :)

  67. Miracrown
    • one year ago
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    @ganeshie8 can you please give us another prob?

  68. Astrophysics
    • one year ago
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    What is \[\huge 2^{2014}-2^{2013}?\]

  69. geekfromthefutur
    • one year ago
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    ok

  70. ParthKohli
    • one year ago
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    \[2^{2013}\]

  71. geekfromthefutur
    • one year ago
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    crap it repeated my statment

  72. ParthKohli
    • one year ago
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    Sorry, wrong answer. Should be\[\huge 2^{2013}\]

  73. ParthKohli
    • one year ago
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    Or maybe you could do it "that" way:\[\large 2^{2014} - 2^{2013} = 2^{2014 - 2013} = 2^1 = 2\]

  74. Astrophysics
    • one year ago
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    Yeah haha, \[\huge 2^{2013}(2) - 2^{2013} \implies 2^{2013}(2-1) = 2^{2013}\]

  75. Miracrown
    • one year ago
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    Next one

  76. Astrophysics
    • one year ago
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    Geniuses...ok what number am I thinking of?

  77. ParthKohli
    • one year ago
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    Your SmartScore.

  78. Miracrown
    • one year ago
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    96

  79. Astrophysics
    • one year ago
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    http://puu.sh/ajiP2/15be9508bf.png

  80. ParthKohli
    • one year ago
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    You're just cashing in on hartnn's efforts.

  81. ParthKohli
    • one year ago
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    In hartnn's pic, his arms are all bulgy and muscular. Coincidence? I think not.

  82. zzr0ck3r
    • one year ago
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    You should read the classic MathEd paper about Benny.

  83. geerky42
    • one year ago
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    \(\color{blue}{\text{Originally Posted by}}\) ganeshie8 How is this possible \[\frac{1}{4}-\frac{3}{8} = \frac{1}{2}\] \(\color{blue}{\text{End of Quote}}\) It's isn't? What's so amazing about it anyway? All I see is user just happen to think that subtraction works like multiplication, hence did\(\frac{1}{4}-\frac{3}{8} = \frac{1-3}{4-8}\)

  84. UsukiDoll
    • one year ago
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    ^ which broke a math rule...

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is replying to Can someone tell me what button the professor is hitting...

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