Today's Puzzle

Page 3 of 17 FirstFirst 1234513 ... LastLast

  1. Posts : 5,440
    Microsoft Windows 7 Home Premium 64-bit 7601 Multiprocessor Free Service Pack 1
    Thread Starter
       #21

    Thank You Arc! You read the puzzle as I meant it to be read! I think it fair to say we are all right!
      My Computer


  2. Posts : 1,397
    Win 10 Pro 64
       #22

    Kari said:
    mitchell65 said:
    There are three discs, Each on has a "7" on one side and an "8" on the other side. If thrown up radomly, how many combinations of numbers is possible. (Example "777" "888" etc)
    2 * 2 * 2 = 8 combinations.
    • 777
    • 778
    • 787
    • 788
    • 877
    • 878
    • 887
    • 888
    I think Kari is correct!
      My Computer


  3. Posts : 53,363
    Windows 10 Home x64
       #23

    My head hurts...

    A Guy
      My Computer


  4. Arc
    Posts : 35,373
    Microsoft Windows 10 Pro Insider Preview 64-bit
       #24

    A Guy said:
    My head hurts...

    A Guy

    :)
      My Computer


  5. Posts : 53,363
    Windows 10 Home x64
       #25

    Badgers? We don't need no stinkin' badgers!!

    A Guy
      My Computer


  6. Posts : 5,440
    Microsoft Windows 7 Home Premium 64-bit 7601 Multiprocessor Free Service Pack 1
    Thread Starter
       #26

    My apologies for this thread! I started it off thinking it would be a bit of fun but it got taken far more seriously than I intended, so no more Puzzles from me!
      My Computer


  7. Posts : 53,363
    Windows 10 Home x64
       #27

    mitchell65 said:
    My apologies for this thread! I started it off thinking it would be a bit of fun but it got taken far more seriously than I intended, so no more Puzzles from me!
    Nah, it's all good, post another, look at the fun everyone had :)

    A Guy
      My Computer


  8. Arc
    Posts : 35,373
    Microsoft Windows 10 Pro Insider Preview 64-bit
       #28

    A Guy said:
    Badgers? We don't need no stinkin' badgers!!

    A Guy
    You have badges, now you dont want badger ..... how can I manage a badgest for you
      My Computer


  9. Posts : 2,663
    Windows 8.1 Pro x64
       #29

    Golden said:
    Kari said:
    mitchell65 said:
    There are three discs, Each on has a "7" on one side and an "8" on the other side. If thrown up radomly, how many combinations of numbers is possible. (Example "777" "888" etc)
    If asked like this, then [Disk 1:7, Disk 2:7, Disk 3:8] is not the same combination than [Disk 1:7, Disk 2:8, Disk 3:7]. The answer is 8 combinations.
    Kari is correct - in statistical theory combinations refers to permutations. Two different numbers on each of 3 disks is expressed as 2!3 (two factorial 3) which is 2 x 2 = 4 x 2 = 8.

    The total number of combinations is 8.
    2!3 isn't mathematically correct and would imply 2!*3, which is in fact 6. I think you mean 2^3, which is how you would calculate the number of outcomes and is 8 :)

    Some of you may have seen this before but I'll share it anyway because I think the maths behind it is fascinating. Given a set of n randomly chosen people, how large does n have to be before the probability of two people sharing a birthday becomes 0.5?

    It's a well known maths problem so googling it will give you the answer in seconds, if you want to ruin it


    Another favourite of mine:

    Let x=y
    Multiply both sides by x:
    x^2=xy
    Subtract y^2 from both sides:
    x^2-y^2=xy-y^2
    Factorise both sides:
    (x+y)(x-y)=y(x-y)
    Divide both sides by (x-y):
    x+y=y
    2y=y
    2=1

    Why is this not true?

    Tom
      My Computer


  10. Arc
    Posts : 35,373
    Microsoft Windows 10 Pro Insider Preview 64-bit
       #30

    Lol, that's a fallacy

    From the equation, we are subject to determine the values of the variables, x and y. Isn't it? Not the values of the constants.

    Taking your calculations, we get
    Let x=y
    Multiply both sides by x:
    x^2=xy
    Subtract y^2 from both sides:
    x^2-y^2=xy-y^2
    Factorise both sides:
    (x+y)(x-y)=y(x-y)
    Divide both sides by (x-y):
    x+y=y
    or, x=y-y
    or, x=0
    putting the value of x in the initial condition, we get
    y=0

    To determine any other values of x and y, we need at least one more equation.

    Number of possible outcomes are calculated as "number of possible outcomes in a trial to the power number of trials".

    Number of possible outcomes for tossing a coin thrice (as good as John's original question) =8 (2*2*2). For throwing a die thrice= 216 (6*6*6). For drawing a card 3 times (with replacement) from a pack = 140608 (52*52*52).
      My Computer


 
Page 3 of 17 FirstFirst 1234513 ... LastLast

  Related Discussions
Our Sites
Site Links
About Us
Windows 7 Forums is an independent web site and has not been authorized, sponsored, or otherwise approved by Microsoft Corporation. "Windows 7" and related materials are trademarks of Microsoft Corp.

© Designer Media Ltd
All times are GMT -5. The time now is 15:30.
Find Us