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Math Help - [SOLVED] Number pyramid

  1. #1
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    [SOLVED] Number pyramid

    [SOLVED] Number pyramid-00.bmp on that the t =3 and i need to fill in the other numbers but i also need to know how to work it out if any 1 can help please post this is different but i need to know if the top number is 42 what is T thank you



    EDIT by Jhevon: Apparently the question was something like this.

    Given that the number in the top box is 42, and that the number in each box (that is not in the base) is given by the sum of the two boxes directly below it, find T.
    Last edited by Jhevon; February 6th 2009 at 04:41 PM. Reason: question unclear
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  2. #2
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    Hello, Andy!

    You didn't give us the rule for filling the boxes.
    I will assume that it is an "additive" sequence . . .


    Code:
                      * - - - *
                      |  42   |
                  * - + - * - + - *
                  |       |       |
              * - + - * - + - * - + - *
              |       |       |       |
          * - + - * - + - * - + - * - + - *
          |   4   |   T   |   3   |   5   |
          * - - - * - - - * - - - * - - - *

    Assuming that each number is the sum of the two numbers below it,
    . . we have this pyramid.
    Code:
                      * - - - *
                      |  42   |
                  * - + - * - + - *
                  | 2T+7  | T+11  |
              * - + - * - + - * - + - *
              |  T+4  |  T+3  |   8   |
          * - + - * - + - * - + - * - + - *
          |   4   |   T   |   3   |   5   |
          * - - - * - - - * - - - * - - - *

    The final "step" would be: . (2T+7) + (T + 11) \:=\:42

    And we get: . 3T + 18 \:=\:42 \quad\Rightarrow\quad 3T \:=\:24 \quad\Rightarrow\quad\boxed{ T \:=\:8}

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  3. #3
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    hi u said

    but t=3 so 2t=6 so 6+7 =13 and 3+11=14 so i dunno how u got 42
    could u explain please
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  4. #4
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    Hello, Andy!

    You still didn't give us any rules!

    I didn't understand the problem.
    We're given that T = 3, right?

    And we're suppose to fill in the pyramid (without knowing how) ?
    . . and figure out the top number?

    Good luck!
    Code:
                      * - - - *
                      |   ?   |
                  * - + - * - + - *
                  |   ?   |   ?   |
              * - + - * - + - * - + - *
              |   ?   |   ?   |   ?   |
          * - + - * - + - * - + - * - + - *
          |   4   |   3   |   3   |   5   |
          * - - - * - - - * - - - * - - - *
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  5. #5
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    Quote Originally Posted by Soroban View Post
    Hello, Andy!

    You still didn't give us any rules!

    I didn't understand the problem.
    We're given that T = 3, right?

    And we're suppose to fill in the pyramid (without knowing how) ?
    . . and figure out the top number?

    Good luck!
    Code:
                      * - - - *
                      |   ?   |
                  * - + - * - + - *
                  |   ?   |   ?   |
              * - + - * - + - * - + - *
              |   ?   |   ?   |   ?   |
          * - + - * - + - * - + - * - + - *
          |   4   |   3   |   3   |   5   |
          * - - - * - - - * - - - * - - - *


    oh ye sorry u can only add
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  6. #6
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    Quote Originally Posted by andyboy179 View Post
    Click image for larger version. 

Name:	00.bmp 
Views:	9 
Size:	947.9 KB 
ID:	9976 on that the t =3 and i need to fill in the other numbers but i also need to know how to work it out if any 1 can help please post this is different but i need to know if the top number is 42 what is T thank you
    i tried a bit i got 27 at the top. not really sure bout it.



    Code:
                      * - - - *
    
                      |  27   |
    
                  * - + - * - + - *
    
                  |   13    |  14     |
    
              * - + - * - + - * - + - *
    
              |   7    |   6    |   8    |
    
          * - + - * - + - * - + - * - + - *
    
          |   4   |   3   |   3   |   5   |
    
          * - - - * - - - * - - - * - - - *
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  7. #7
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    Quote Originally Posted by princess_21 View Post
    i tried a bit i got 27 at the top. not really sure bout it.
    ye thats what i got
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  8. #8
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    Question

    Quote Originally Posted by andyboy179 View Post
    ye thats what i got
    so where do you get 42? is that the right answer?
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  9. #9
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    Quote Originally Posted by princess_21 View Post
    so where do you get 42? is that the right answer?
    know the first bit of what u said about 27 that was the first question

    the second question was about the 42 the question is if the top number is 42 what will T=
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  10. #10
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    Question

    Quote Originally Posted by andyboy179 View Post
    know the first bit of what u said about 27 that was the first question

    the second question was about the 42 the question is if the top number is 42 what will t=
    t= 8

    Code:
                      * - - - *
                      |  42   |
                  * - + - * - + - *
               |     23 |   19    |
              * - + - * - + - * - + - *
        |   12    |  11    |   8    |
          * - + - * - + - * - + - * - + - *
      |    4   |   8  |   3    |   5   |
          * - - - * - - - * - - - * - - - *
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  11. #11
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    Cool

    i got a formula from that pyramid try putting variables there.

    Code:
                      * - - - *
                      |  42   |
                  * - + - * - + - *
                  |   d   |   e   |
              * - + - * - + - * - + - *
              |   b    |   c    |   8   |
          * - + - * - + - * - + - * - + - *
          |   4   |   a   |   3   |   5   |
          * - - - * - - - * - - - * - - - *
    4+a=b
    a+3=c
    c+8=e
    b+c=d
    d+e=42

    d+e=42

    (b+c)+(c+8)=42

    (4+a)+(a+3) +(a+3) +8 =42

    3a+18=42

    3a=24

    a=8
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  12. #12
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    by the way Andy, I didn't realized that Soroban already answered your question.. t=8. you should thank him too.
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  13. #13
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    Hello, andyboy179!

    The second question was about the 42
    The question is: if the top number is 42, what will T equal?

    That's the question I answered first! . . . Didn't you read my response?

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  14. #14
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    Quote Originally Posted by Soroban View Post
    Hello, andyboy179!


    That's the question I answered first! . . . Didn't you read my response?

    yes i did read ur response but i read it wrong i thought u were on about the first question sorry if i have offended u
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