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jasen

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Posts posted by jasen

  1. 7 hours ago, jhawk said:

    First of all you don't proofread your typing,if you go right or left A cells, go up or down B cells

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    your cell number is X*Y  each or the 4 numbers generated will be ( X+A ) ,or (X-A) ,times (Y+B), or (Y-B).  Add the 4 numbers and you get 4XY

     

     

    sorry if my words is confusing.
    I mean go right (or left) from last position.

    your answer is close but still wrong.
    If I draw from your answer, the shape will be a rectangular on a flat surface.
     _______
    |       |
    |   x   |
    |_______|

  2. create a m x n table.
    then put the multiplication result of x,y coordinate in each cell.

    set any cell as your preffered base.
    from the base go up    A steps, then go right (or left) B steps, take the number as num1
    from the base go left  A steps, then go right (or left) B steps, take the number as num2
    from the base go down  A steps, then go right (or left) B steps, take the number as num3
    from the base go right A steps, then go right (or left) B steps, take the number as num4

    (num1 + num2 + num3 + num4) / 4 = your number.

    anybody can explain this ?

    Unti.jpg

  3. On 2/18/2016 at 7:33 PM, sujith said:

    How and why

     

    B: see 4, there are 2 possibility : 1 x 4 or 2 x 2. so B do not know the 2 numbers
       so B first say "No"

    A: see 5, there are 2 possibility : 1 + 4 or 2 + 3.
       From B answer, A still can't deduce the 2 numbers.
       if B see 6 (2*3) B will say No (2 possibility 1*6,2*3)
       if B see 4 (1*4) B will say No (2 possibility 1*4,2*2)
       so A say "No"

    B: From A answer
       if A see 4 from (2*2) there are 2 possibility : 1 + 3 or 2 + 2.
       but A must say yes, because if the numbers are 1 and 3, B will answer "yes" imediately
       so A must deduce the numbers are 2 and 2 in the first try.

      So A must be see 5, and B deduce the numbers must be 1 and 4

  4. Ok, maybe my question is not specific enough.

    - There is only one room, not hotel.
    - The man inside the room, is giving information to his friend outside the room, by pushing the bell button once.
    - there is only 1 bell, and it just ring, not stated something.
    - The man inside the room, can't control how long the bel ring.
    - the number is between 0 and 100.

  5. 13 hours ago, Logophobic said:

    1+6+9+5+12 = 5+12+10+4+2, as required: A+B+C+D+E = D+E+F+G+H

    Of course, A+B+C+D+E = F+G+H+I+J does seem more appropriate, but I was working with what you posted.

    Ok, I just realize my question was wrong, yes it should be A+B+C+D+E = F+G+H+I+J 

  6.  

    9 hours ago, Logophobic said:

     

    Very good start, your second answer is right, 
    but the first answer is wrong, because 1+6+9+5+12 =/= 10+4+2+8+3.


    We can easily find the other right answer from the first right answer.
    use your second answer to find another right answer (ofcourse without rotation and reflection)
    hint : put the inner points to the outer points.

     

  7. B : No
    A : No
    B : Yes

    Spoiler

     

    B: see 4, there are 2 possibility : 1 x 4 or 2 x 2. so B do not know the 2 numbers
       so B first say "No"

    A: see 5, there are 2 possibility : 1 + 4 or 2 + 3.
       From B answer, A still can't deduce the 2 numbers.
       if B see 6 (2*3) B will say No (2 possibility 1*6,2*3)
       if B see 4 (1*4) B will say No (2 possibility 1*4,2*2)
       so A say "No"

    B: From A answer
       if A see 4 from (2*2) there are 2 possibility : 1 + 3 or 2 + 2.
       but A must say yes, because if the numbers are 1 and 3, B will answer "yes" imediately
       so A must deduce the numbers are 2 and 2 in the first try.

      So A must be see 5, and B deduce the numbers must be 1 and 4

     


     

  8. @bonanova. How do you get the numbers?

     
    My answer is very close to your answer for 6 digits numbers. 
    If I search the numbers by computer start from 000000 to 999999 the result is exactly same with your calculation. (although maybe it is not the best answer)
     
    ["000000","011111","022222","033333","044444","055555","066666","077777","088888","099999","101234","110325","123016", "132107","145670","154761","167452","176543","202318","213209","220153","231042","246735","257624","264580","275491","303145","312054", "321360","330271","347506","356417","365723","374632","404826","415937","428405","439514","480649","491758","506951","517840","529687","538796", "581473","590562","608579","619468","626894","637985","684257","695346","724978","735869","748021","759130","786302","797213","842963", "853872","962831","973920"]
  9. Find the maximum number of distinct ways you can create combination of six digit number
    (from 0 through 9). with following rules :

    1. Each number can be used more than one. 
    2. Any two combinations can have at most 1 digit in same place.

    example :
    a. 075922 and 166433 is accepted.
    b. 075922 and 166432 is accepted, both put 2 in 6th place).

    c. 075922 and 066432 cannot both be used,
       because both put 0 in first place, and 2 in 6th place).
     

  10. I think I have found the answer

    Spoiler

     

    I just found intersting connection 

    (a+b)5 + (a-b)=  (a5 + 5a4b + 10a3b2 + 10a2b3 + 5ab4 + b5 ) + (a5 - 5a4b + 10a3b2 - 10a2b3 + 5ab4 - b5 ) = 2a5 + 20a3b2 + 10ab4

    there you don't have to count odd exponent of b. 

    after I tried it in haskell,  (3 + √5)n  + (3 - √5)n  is very close with (3 + √5)n

    so just count (3 + √5)n  + (3 - √5)n, with above ways and substract the value with 1. 

    example : 

    (3 + √5)4 = 751.6594202199647

    (3 + √5)4  + (3 - √5)4 = 752

     

    (3 + √5)5 = 3935.739820199815

    (3 + √5)5  + (3 - √5)5 =  3936

     

     

  11. First count (sqrt 5), in very high precision.

    Then use pascal triangle formula.

    then group every odd exponent of sqrt (5). then multiple it by (sqrt 5) just once, you will get right answer.

    you will get better precision.

    example

    (a+b)5 = a5 + 5a4b + 10a3b2 + 10a2b3 + 5ab4 + b5

             = a5 + b(5a4 + 10a2b2 +b4) + 10a3b+ 5ab4

    (3 + √5)5 = 35 + √5(5.34 + 10.32.5 + 25) + 10.33.5+ 5.3.25 = 1968 + √5*880 

  12. Solution :

    Spoiler

     

    I call it Another "Easy" Puzzle, because it have a strong connection with my first question (Easy Puzzle).

    use solution from my first answer :  A = 1, B = 5, C = 6, D = 3, E = 2, F = 7

    then write it like this :A = 21 , B = 25 , C = 26 , D = 23 , E = 22 , F = 27

    so (A,B,C,D,E,F) = (2,32,64,8,4,128)

    This works by the Exponent Laws: xm * xn = xm+n

     

     

  13. You meet 4 persons, at least one of them always tell the truth, and the other always lie.

    Then you have conversation with them.

    Andre  : I, Brian and Cole are truth-tellers, Diego is a liar.
    Brian  : I'm truth-teller, Andre and Cole are liars.
    Cole   : I, and Andre are truth-tellers, other are liars.
    Diego  : I, and Andre are truth-tellers, Brian is a liar.

    Identify the liars and truth-tellers.

  14. Another "Easy" Puzzle

    Find The value of x and y, then put numbers 2,4,8,32,x,y to each point, so :

    I.  The product of points in every circle  are equal,  (A*E*F*C = B*E*D*C = A*D*F*B)
    II.  A*B*C = D*E*F

    There are 2 solutions (Reflection and rotation solutions are considered as 1 same solution)

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