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BMAD last won the day on August 31 2017

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About BMAD

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  • Birthday 02/26/1980

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  1. excellent work as always bonanova but should
  2. BMAD

    Two boys

    ah, thank you.
  3. BMAD

    Two boys

    Alas, English.... But I am confused. From your interviewing you know for a fact that this family has A boy. So regardless of their birth order all we don't know is the probability that the other child is a boy. And the other child could be a boy or girl, so I still believe it is 1/2.
  4. BMAD

    Two boys

    If it is given that they already have one boy then... I get 1/2. Since the second child could either be a boy or a girl. Note: The spoiler buttons seems to be missing on mobile again.
  5. Assume we have a circle and a rectangle. The circumference of the circle is the same as the perimeter of the rectangle and the areas of each shape is also the same. Write the ratio of the circle's circumference to the diagonal of the rectangle as a function in terms of the width of the rectangle.
  6. BMAD

    a^b x c^a = abca

    I hope there is a nuanced way of solving this besides brute force.
  7. BMAD

    Limit of a shrinking function

    The first case
  8. Find the limit of x^(x/2)^(x/4)^(x/8)^(x/16)^(x/32).... (a) as x goes to infinity (b) as x goes to zero
  9. BMAD

    Balancing weights

    but if you place 3,4 on one side it would not be balanced.
  10. BMAD

    I want the butterscotch

    To answer your second part: the machine would scan the candies and intentionally pick out a butterscotch and randomly select four candies from the remaining four. So in this case, if there is a butterscotch candy left then you are guaranteed that the first one chosen was a butterscotch.
  11. BMAD

    Help Bob find Alice's P(x)$%^

    n is not known
  12. Alice and Bob are playing the following game: Alice has a secret polynomial P(x) = a_0 + a_1 x + a_2 x^2 + … + a_n x^n, with non-negative integer coefficients a_0, a_1, …, a_n. At each turn, Bob picks an integer k and Alice tells Bob the value of P(k). Find, as a function of the degree n, the minimum number of turns Bob needs to completely determine Alice’s polynomial P(x).
  13. BMAD

    Is it a factor?

    Consider the set {1,11,111, …, ((10^2007) – 1)/9}. At least one of these numbers is divisible by 2007. Is the same true for 2008 (replacing 10^2007 with 10^2008, of course)?
  14. BMAD

    Code to the safe

    You have 7 generals and a safe with many locks. You assign the generals keys in such a way that EVERY set of four generals has enough keys between them to open ALL the locks; however, NO set of three generals is able to open ALL the locks. How many locks do you need, and list how many keys does the first general get, the second, … Is there more than one way that works?