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DejMar

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Posts posted by DejMar

  1. A list of 287, such that each letter appears later in the alphabet to those that precede it in the word:

    ABET     BEGIN    CHIMPS   DEITY    EMPTY    GNOW   
    ABHOR    BEGINS   CHIN     DELO     ENOW     GORSY  
    ABHORS   BEGIRT   CHINO    DELOS    ENVY     GORY   
    ABLOW    BEGO     CHINOS   DELS     ERST     HILT   
    ABLY     BEGOT    CHINS    DELT     ERUV     HIMS   
    ABORT    BEGS     CHINT    DEMO     FIKY     HINS   
    ABOS     BEIN     CHINTZ   DEMOS    FILM     HINT   
    ACER     BEKNOT   CHIP     DEMPT    FILMS    HIPS   
    ACERS    BELOW    CHIPS    DEMY     FILMY    HIPT   
    ACES     BELS     CHIRT    DENS     FILO     HIST   
    ACHY     BELT     CHIRU    DENT     FILOS    HOPS   
    ACKNOW   BENS     CHIS     DENY     FILS     HORS   
    ADEPT    BENT     CHIT     DEOXY    FINO     HORST  
    ADIOS    BENTY    CHIV     DERV     FINOS    HORSY  
    ADIT     BEST     CHIVY    DEWY     FINS     HOST   
    ADOPT    BEVY     CHIZ     DEXY     FIRS     IMPS   
    ADOS     BIJOU    CHOP     DHOW     FIRST    JORS   
    ADRY     BIJOUX   CHOPS    DIMP     FIST     KNOP   
    AEGILOPS BINS     CHOU     DIMPS    FISTY    KNOPS  
    AEGIR    BINT     CHOUX    DIMPSY   FLOP     KNOT   
    AEGIS    BIOPSY   CHOW     DIMS     FLOPS    KNOW   
    AERY     BIOS     CIST     DINO     FLOR     KOPS   
    AGIN     BIRSY    CITY     DINOS    FLORS    KORS   
    AGIO     BIST     CLOP     DINS     FLORY    KORU   
    AGIOS    BLOT     CLOPS    DINT     FLOW     LOPS   
    AGIST    BLOW     CLOT     DIPS     FLOX     LORY   
    AGLOW    BLOWY    CLOU     DIPT     FLUX     LOST   
    AGLU     BOPS     CLOW     DIRT     FOPS     MOPS   
    AGLY     BORS     CLOY     DIRTY    FORT     MOPSY  
    AHINT    BORT     COPS     DITZ     FORTY    MOPY   
    AHIS     BORTY    COPSY    DIXY     FOXY     MORS   
    AHOY     BORTZ    COPY     DOPS     GHIS     MORT   
    AILS     BOXY     CORS     DOPY     GHOST    MOST   
    AIMS     BRUX     CORY     DORS     GHOSTY   MOTU   
    AINS     CEIL     COST     DORT     GILPY    MOXY   
    AIRS     CEILS    COSY     DORTY    GILT     NOSY   
    AIRT     CELS     COWY     DORY     GIMP     NOWY   
    AIRY     CELT     COXY     DOST     GIMPS         
    AITU     CENS     CRUX     DOTY     GIMPY         
    ALMOST   CENT     DEFI     DOUX     GINS          
    ALMS     CENTU    DEFIS    DOXY     GIOS          
    ALOW     CEPS     DEFO     DRUXY    GIPS          
    ALPS     CERT     DEFT     EGIS     GIPSY         
    AMORT    CERTY    DEFY     EGOS     GIRT          
    AMPS     CHIK     DEGS     EIKS     GIST          
    ANOW     CHIKOR   DEGU     ELMS     GLOP          
    ARSY     CHIKORS  DEHORT   ELMY     GLOPS         
    ARTY     CHIKS    DEIL     ELOPS    GLORY         
    BEFIT    CHIMO    DEILS    EMOS     GLOST         
    BEGILT   CHIMP    DEIST    EMPT     GLOW          

     

     

    • Upvote 1
  2. Spoiler

    Without changing the arrangement of the letters, I found only four strings of animals:

    SUPERNATURAL ANIMALS : honey buzzard
    SUPERNATURAL ANIMALS : sea eagle
    SUPERNATURAL ANIMALS : Caucasian mountain wild goat
    SUPERNATURAL ANIMALS : black tropical American cuckoo


     

  3. Spoiler

    Quarter is given to be not a portion of the measure or that which is measured, thus it is the measurement, and subsequently, the stone is the material being measured. A quarter is 28 pounds weight, which is approximately 196000 grains. A dram can be anything small, which in this case is the substance of stone. One grain is 1/196000 quarter of stone, and can be said to literally be a grain of sand.

     

  4. Spoiler

    There are two possible sets of eight words:
      PIER, LADS, SENT, TORE, SILL, NAPS, RENT, HOSE
    and
      LIER, SADS, TENT, SORE, NILL, RAPS, HENT, POSE

    PIER - buttress                         LIER - a person who lies down
    LADS - young men                        SADS - expresses sadness
    SENT - dispatched                       TENT - portable shelter
    TORE - rent                             SORE - tender
    SILL - windowsill                       NILL - not to wish
    NAPS - sleeps briefly                   RAPS - strikes
    RENT - torn                             HENT - sieze
    HOSE - flexible pipe                    POSE - pretend

     

    • Upvote 1
  5. Joyandwarmfuzzies wrote:

    "Per the Pythagoren Theorem, 4ac must also be a square, which only occurs when a = c."

    4ac may be a square other than when a = c. It is a square when all the factors of 4, a and c can be paired up (4 is is paired up with factors 2*2). As each "a" and "c" are given as odd, neither will have the prime factor 2 as a factor. Yet, "a" may have, for example, the factors 3*3*3 and "c" may simply have the factored 3. This would allow 4ac in this given example to be the square of 18 (=2*3*3).

  6. "As soon as there are martians at points A,B,C such that triangle ABC contains the center of the field..."

    Are the three points, A,B,C any set of three random points on the circumference of the field from an increasing permutation of triangles that would enclose the field's center? That is, if Farmer Brown has not been transported after the appearance of three alien zoologists, a,b,c, but, a minute later, a fourth martian, d, landed, there are four permutations of triangles, such that zero, one or two of the four permutations that involve the four landed martians form triangles that enclose the field's center point. Would each of the triangles that enclosed the field's center be considered triangle ABC (I.e., more than one triangular transportation zone might exist)?

    Is it possible that a martian may land on an already occupied point [a Dorothy-Gingema event], and are martian's considered point-like beings for calculation of the probability?

     



  7.  

    n! + 1 is prime for n = {0, 1, 2, 3, 11, 27, 37, 41, 73, 77, 116, 154, 320, 340, 399, 427, 872, 1477, 6380, 26951, 110059, 150209}
    Other factorial primes n! + 1 may exist, yet none have been found (as prior to May 2014). From the generally accepted mathematical definition of composite, most other values of the natural numbers n! + 1 are composite. That is, within the domain of natural numbers, bonanova's guess, Aleph-0, is likely correct.
    .
  8.  

    "Composite" refers to the number having at least two distinct positive integer divisors.

     

    Actually, that's not quite true as 1 is also a positive integer divisor.

    Composite really just means "not prime".

     

    Not quite true.  "The number one is a unit; it is neither prime nor composite."  Prime and composite are terms that are applied to positive numbers (though the definitions can been extended to include negative numbers -- as associates to the positive, i.e., the negative number is deemed the same prime or composite as the positive number by the extended definition [refer to the Prime Pages FAQ "Can negative numbers be prime?"]). A composite number has been defined as any positive integer that has at least two prime factors.

  9. Roll the d977 and the d709.
    977*(d709-1)+d977 [or, alternately, 709*(d977-1)+d709] provides the range of 1 to 692693.
    If the result is 692693, re-roll, else divide by 692, and take the ceiling of the result.

    A re-roll will occur 1/692693 (approximately 0.00014436%) for each roll.

     

    Edit - I see after the fact that Rainman already found this answer.

  10. Label the faces of the 79-sided die from 1 to 77, with two faces marked re-roll.


    Label the 13-sided die from 0k to 12k, where k=77.

    Roll the two dice and add the faces, re-rolling the 79-sided die if so indicated.
    There is a 2/79, i.e., approximate 2.5316% chance of a re-roll required after each roll, but an approximate 97.4684% chance that the two-dice will result in the random integer required in the first roll.
  11. Given that non-alphabetic letters are used except for the blank (space) to separate the "words",

    Given that there are no non-alphabetic characters used, except for the blank (space) used as a word separator,

    27x27x27x26 is not the correct solution; nor is 26x25x24x23 as had been selected as the best answer.

    The correct count is  26x26x26x26 + 26x26x26 + 26x26 + 26.

    a,b,c,d,e,f,g,...,x,y,z  = 261 = 26 "words" of 1 letter.
    aa,ab,ac,ad,...,zx,zy,zz = 262 = 676 "words" of 2 letters.
    aaa,aab,...,zzx,zzy,zzz  = 263 = 17,576 "words" of 3 letters.
    aaaa,aaab,...,zzzy,zzzz  = 264 = 456,976 "words" of 4 letters.
    ---------------------------------------------------------------------------
     456,976 + 17,576 + 676 + 26 = 475,254 different "words",

    thus the magnetic tape does not contain all different "words". At least 24,746 "words" are duplicates

    .

  12. There is no given restriction on the alphabet/s that is/are used, thus all 500,000 "words" could be different. 


    The modern English alphabet has 26 letters, yet there are letters of other alphabets that are sometimes used in English, such as ash (Æ), oethel (Œ), and schwau (Ə). In the early modern English alphabet, the ampersand (&) - that is, and, per se, and, was once considered one of the letters of the alphabet, though it was generally used alone, but also possibly in some compound words.

    Limited to the 26 letters of the modern English alphabet, absent hyphens and other symbols, there are 475,254 different words possible.  For a set of 27 letters, absent other symbols, there are 551,880 different words possible. Hence, the answer to the given problem is subject to a definition of what set of letters/characters/symbols are permitted, and what defines a "letter".

  13. Three dice will do the trick.



    Take the 7-, 11-, and 13-sided dice.

    7*11*13 = 1001, thus, a random integer may be generated uniformly between 1 to 1001, inclusive, using these dice.

    Let the faces of the 13-sided die be numbered: 0, 77, 154, 231, 308, 385, 462, 539, 615, 693, 770, 847, and 924.
    Let the faces of the 11-sided die be numbered: 0, 7, 14, 21, 28, 35, 42, 49, 56, 63, 70.
    Let the faces of the 7-sided die be numbered: 1, 2, 3, 4, 5, 6, 7.

    Roll the three dice, summing the numbers on each of the dice for the random integer.

  14. Your set of three words could be one of the following:
     

    AEI + DM = (1) AIMED, (2) AMIDE, (3) MEDIA

    AEI + DS = (1) AIDES, (2) ASIDE, (3) IDEAS

    AEO + DR = (1) OARED, (2) ADORE, (3) OREAD

     

    As the game involved was Scrabble, the first set has the highest point value, though the second set has the best chance of hooking for a high score.


  15.  

    A polynomial of the form (ac)x

    2 + (ad + bc)xy + (bd)y2 + (an + mc)x + (bn + md)y + mn can be expressed as having the factors
    (ax + by + m) and (cx + dy + n).

    Equating the coefficients of the polynomial 2x2 + 3xy - 2y2 - x + 3y - 1 to the expression above:
    A:  2 = ac
    B:  3 = ad + bc
    C: -2 = bd
    D: 1 = an + mc
    E: 3 = md + bn
    F: -1 = mn

    WLOG, and seeking only integer coefficients, let m = 1, n = -1
    from (E) 3 = d - b, thus, d = b + 3
    substituting into ( C),
    -2 = b(b + 3)
    0 = b2 +3b + 2, which factors to
    0 = (b + 2)(b + 1)
    b = {-1, -2}
    therefore, by again substituting into © and solving
    d = {2, 1}

    b = -1, d = 2         b = -2, d = 1
    3 = a(2) + (-1)c      3 = a(1) + (-2)c
    3 = 2a - c            3 = a - 2c

    substituting (A), a = 2/c,
    3 = 2(2/c) - c        3 = (2/c) - 2c
    multiplying both sides by c and factoring
    c2 + 3c - 4 = 0      2c2 + 3c - 2 = 0
    (c + 4)(c - 1) = 0    (2c - 1)(c + 2) = 0
    c = {-4, 1}           c = {1/2, -2}
    therefore,
    2 = a(-4)  2 = a(1)   2 = a(1/2)  2 = a(-2)    
    a = -1/2   a = 2      a = 4       a = -1

    Ignoring the non-integer coefficients, the factors are then
    G: (2x - y + 1)(x + 2y - 1), or
    H: (-x - 2y + 1)(-2x + y - 1)

    (H) is the same as (G) but with each factor multiplied by -1, thus
    the factors for the equation can be simply given as
    (2x - y + 1), (x + 2y - 1)
  16. There are two sets of four distinct natural numbers {a,b,c,d} where a*b = c*d = a+b+c+d: {2,15,3,10} and {2,12,4,6}. This is, of course, in addition to the sets of the same numbers ordered differently, i.e., swapping values between the mutliplicands of one expression.or the swapping of the pair with that of the other pair, such as (15, 2, 10, 3).



    There is no set of four distinct natural numbers where a*b = c*d = a*d = a+b+c+d, as a*d = c*d would mean that a = c, and a*b = a*d would mean b = d, both of which contradict the given that the natural numbers are distinct. 


  17.  

    An assumption is made that strength and endurance is not altered between contests, no forces


    other than a team's combined strength favors either team, and each player puts forward a best
    effort to win for their assigned team. An additional assumption is made that the players of
    the two mini-teams are the same lost players in which their contest results in a draw.

    A+B+C+D+E > F+G+H+I+J (3)
        C+D+E = H+I+J     (4)
          A+B > F+G       (4)
          A+F < B+G       (5)
    -------------------------
            F < G

  18. When taking half the terms of S, the rate at which the infinite series of terms approached 0 was doubled. In addition, the first term of one series of terms, i.e., 1/2, is also set aside before matching up the terms for subtracting one expression from the other, as if the infinite series of the half terms had one more term than the infinite series of the original expression.


    Consider the series as finite:
    S = 1/2 + 1/3 + 1/4 + 1/5 + 1/6 + 1/7.
    1/2 S = 1/4 + 1/6 + 1/8 + 1/10 + 1/12 + 1/14
    Subtracting 1/2 S from S
    1/2 S = 1/2 + 1/3 + 1/5 + 1/7 + (-1/8 -1/10 -1/12 -1/14)
    Note, there are subtractive terms that have been failed to be expressed by the problem's falacial logic. In the infinite series where one 1/2 S expressions is subtracted from the other, these subtractive terms will total to the negative equivalence of the sum of the addititive terms, thus the the left-hand side of the expression is not the falacial something, but also is nothing (zero).


  19.  

    The hypotenuse leg theorem gives that if the hypotenuse of two right triangles are congruent (AX ≡ AX) and a corresponding leg of each are congruent (XB* ≡ XC*), then the triangles are congruent, hence the other legs are also congruent (AB* ≡ AC*). Yet points B and C are not given as equally distant from point A as are the pair of points B* and C*. Furthermore a×b = c×d does not imply |a-b| = |c-d|.




  20.  

    A flaw is that when the hypotenuse leg theorem is introduced, it equates the (cross-)product of a point and a line with that of another point and line. In the preparatory statements, A, B, or C are defined as points and B* and C* are defined as lines (i.e., line segments). A point is of zero length, thus 0×B* = 0×C*, but the conclusion BB* = CC* does not follow, as the notation BB* and CC* has not been properly defined. If B* were defined as the other endpoint, along with X of a line segment that could be denoted as XB*, then BB* would then could be assumed to be the notation of a line segment. But then BB* would not be either the hypotenuse or leg of any defined right triangle, and thus the introduction of the hypotenuse leg theorem would not follow. A flaw is then using improper, undefined, or inconsistent notation

  21. "curve" sequence [Fibonacci (2n+1)-1 : n ∈ ℤ

    + ] 1, 4, 12, 33, 88, ...

    n = 4
    List of points only:
    {A}, {B}, {C}, {D}, {A,B}, {A,C}, {A,D}, {B,C}, {B,D}, {C,D}, {A,B,C}, {A,B,D}, {A,C,D}, {B,C,D}, {A,B,C,D}

    List of line segments only:
    {AB}, {AC}, {AD}, {BC}, {BD}, {CD}, {AB,CD}

    List of points and line segments mixed:
    {AB,C}, {AB,D} {A,BC}, {BC,D}, {A,CD}, {B,CD}, {A,BD}, {AC,D), {A,B,CD}, {A,BC,D}, {AB,C,D}
  22. Seeing the answer given as (1+sqrt(5))*5, I decided to use the trigonometric identities and a table of exact trigonometric values to express 10·√(2 - 2·cos(3π/5)) without the trigonometric function.

    As cos(2u) = 2·cos2(u) - 1, and (3π/5) = 2·(3π/10), u can be equated to (3π/10).

    cos(2·((3π/10)) = 2·cos2(3π/10) – 1, which, as cos(3π/10) = √((5 - √5)/8), the expression can be further be simplified as ¼·(1 - √5).

    Thus, 10·√(2 - 2·cos(3π/5)) = 5·√(6  + 2·√5) = 5·√(1 + √5)2 = 5·(1  + √5), which is the same as the answer presented in post #5.

  23. If the distance between a and j are equal to the distances of of the given pair distances being equal, then the chord length (the straight line between two points on a circle) of AB will equal 10*√(2 - 2*cos(3π/5)), which is approximately 16.18034.



    The distance between a and j can also be greater or lesser than the distances between the other points, but without any other information, for those two cases the exact distances between A and B is indeterminable. If the distances are rounded between the other pairs of points after determining the distances between the ten points, then the distance between a and j, of course, will not equal the others.
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