The Past Master Club
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SOLVING LOGIC PROBLEMS

PROBLEM 1:
Five school chums have 1st names A, B, C, D & E
  with sur names K, L, M, N & P
  who were representative of class F, G, H, I or J .

Using the 5 clues below solve for each ID and class Rep.
  1. "I"'s Rep, who isn't "K" or "L", is neither "A" nor "D".
  2. "E" isn't "N" and didn't Rep class "G".
  3. "E", "H" and "BK" are different class Reps
  4. "P" is class "F"'s Rep.
  5. "M", who isn;t "A", is class "G"'s Rep.

    1. From 1:I / K / L & I / A / D[Reps]
    2. From 2:E (=\N) / G [Reps]
    3. From 3:E / H / BK [Reps]
    4. From 4:PF [Reps]
    5. From 5:MG / A [Reps]
    NOTE: (1) B=K from[c] (2) P=F from[d] (3) M=G from[e] (4) J=K after H=\K from[c] & I=\K from[a] & FP + GM from (2/3) (5) I=N after FP from[d] & GM from[e] & I =\K =\L from[a] (6) H=L left over! (7) E=P after E=\HL from[c](6) & BK from[c](1) & E=\N + GM from(b) (8) C=N after A=\IN & D=\IN from[a](5) & BJK from(1/4) & EFP from(2/7) (9) A=L=H after A=\INC from[a](5/8) & BKJ from(1/4) & EPF from(2/7) & A=\GM from[e] (10) D=M=G left over!
See grid below:

 KLMNP FGHIJ
Ac9e\6||| |||\3*a|||
B1cccc \4\4c\48
Cc====8||| |||||||||*|||
Dc|||10\6||| |||*|||a|||
Ec\5\3b7 8bc\6|||
Fdddd2 
Gee3ed 
H\16e==d 
Iaae5d 
J4==e==d 
SOLUTION
1stSURCLASS
ALH
BKJ
CNI
DMG
EPF
A LITTLE MORE DIFFICULT:
PROBLEM 2:
Five school chums have 1st names A, B, C, D & E
  with sur names K, L, M, N & P
  who were representative of class F, G, H, I & J
  at the age of 19, 20, 21, 22 & 30.

Using the 6 clues below solve for each ID and class Rep.

  1. "C", who isn't "P", isn't class "H"'s Rep.
  2. "H"'s Rep is 1 year younger than "P",
    but older than "D".
  3. "F"'s Rep is younger than "M"
    who is younger than "I"'s Rep,
    who isn't "B" .
  4. "E", who isn't "G"'s Rep, is younger than "K".
  5. "F"'s Rep isn't "N" and is neither "D"'s nor "G"'s Rep.
  6. "J"'s Rep is older than "A" who isn't "K".

    1. From 1: C(=\P) / H [Reps]
    2. From 2: D / H | P [age]
    3. From 3: F / M / I(=\B) [age]
    4. From 4: E(=\G) / K [age]
    5. From 5: F(=\N) / D / G [Reps]
    6. From 6: A(=\K) / J [age]
    NOTE I EXPECT ONLY 1 SOLUTION: (1) D(=\G)(=\F) / H / P / C [Reps] from[a/b/e] (2) D(=I/J) [Reps] from[a/b/e] i. but if D=I then D=I=21 &
    F19 / M20 / ID21 / H22 | P30 [age] from[b/c] a. FC19 / M20 / ID21 / H22 | P30 [age] from[a] b. F19 / MC20 / ID21 / H22 | P30 [age] from[a] 1. FEL19/MCG20/IDK21/HNA22|PJB30 OK[age] from[d/e/f] 2. FE19 / MC20 / ID21 / HK22 | P30 [age] from[d] ii. but if D=J then A(=\K) / DJ / H | P [age] from[b/f] a. A(=\K) / DJM / H | P [age] from[b/f] b. A(=\K) / DJ / HM | P [age] from[b/f] (3) E(=\G) / K(=\J) / A / J [age] from[d/f] Entering above data a-f into grid below:

KLMNP1920212230FGHIJ
Af........f....f
B.............c.
C....a.......a..
D....bX1..bbeeb..
Ed........d.d...
F..ceX4...cc
G..........
H....bbX2a(1)b
I.....cc...
J.....f....
19d.c.b
20....b
21....X3
22.....
30..c..

NOTE: D19: Since (=) e/e/b/// & (=) ///b/c/f Thus D19 has no solution on super imposing ==> X1. And since D / H / P [age] from [c]   then H20 is eliminated ==> X2   and P21 is eliminated ==> X3. Now, like D19,   FP has no solution ==> X4;   - later \1a from [c] Now, since H=\19 [b]; H=\20 [X2];   H=\21 [a]; & H=\30 [b]; thus H=22. Now we can start solving the grid,   below!

KLMNP1920212230FGHIJ
Af\7\7(7b)|||====|||(7)f\7\7(7c)\7f
B\2\2\2\2(2a)====|||==(2)..\2c.
C\6..\5a..|||\1\1a..a..
D(6b)\4==\5bX1\1(1b)bbeeb..
Ed..||||||..|||d\6d.d|||..
F==(4a)ceX4(3b)\3,c\3,ccc
G\6..\5.|||(8)|||||||||
H======(5a)bbX2a(1)b
I(6a)====\5==cc(3)|||\2
J\6..\5.f\7,f||||||(7a)
19d(4)c\3bb
20====(3A)==b
21(6)|||\3|||X3
22X5|||\3(5)\1.b
30====c==(1a)

NOTE:
  1. (1a) is not "C" from [a]; leading to (2) and (2a).
  2. K=\22=(1) has no solution ==> X5
  3. (2) is not "I" from [c]; leading to (3) and c leads to (3a) & (3b) from [age].
  4. (3b) is not "N" from [e]; leading to (4) and (4a).
  5. (5) & (5a) obvious leading to (5a).
  6. (6) obvious leading to (6a) & (6b).
  7. (1) is not "C" from [a] and (6) is not E22 from[d] leading to ==> (7)=22=A.
I leave the rest of
  the solution to you!

SOLUTION
1STSURCLASSAGE
ANH22
BPJ30
CMG20
DKI21
ELF19
HERE IS ONE WITH TOO MUCH INFO ON DAYS!
PROBLEM 3:
Five school chums have 1st names A, B, C, D & E
  with sur names K, L, M, N & P;
  each is a Reps in rooms 100, 150, 200, 250 or 300
  who holds a meeting once a week
  during subject F, G, H, I or J.

Using the 6 clues below solve for each ID,
  room # and week day.
  1. Subect "I" is held 3 days before "A"'s session
      which is held in a room #
      that is twice "N"'s Rep room #.
  2. "C"'s Rep room # is higher than WED's Rep room #.
  3. Subject "G" is held before Rep "L"'s,
      but after Rep "B"'s.
  4. Room 250, which isn't Rep'd by "C",
      holds its session the day before Rep "D"'s.
      who holds his session the day before Rep "H"'s.
      who holds his session the day before Rep "P"'s.
  5. The session in Room 150 is held before Rep "M"'s.
      who holds his session atleast 2 days before Rep "E"'s.
  6. Rep "J" holds his session before THUR's
      which has a room # twice that of "J"'s Rep room #

    1. From 1:I | | | A (=2 x N) [days]
    2. From 2:'WED' / C [#]
    3. From 3:B / G / L [days]
    4. From 4:250(=\C) | D | H | P[days]
    5. From 5:150 / M | / E [days]
    6. From 6:J / 'THUR' (=2 x J) [days]
    NOTE:
    THUR's room # can't be "A" (=2xN)
    else it has 2 numbers
    200 & 250 from [f, a]
    SHOWING ALL PERMUTATIONS BELOW:
    PERMUTATION 1
    MONTUEWEDTHU
    2x
    FRI
    250DHP
    I xAA
    150M ExE
    no solution for MON
    .
    PERMUTATION 2
    MONTUEWEDTHU
    2x
    FRI
    250DHP
    I xAA
    150M=/C ExE
    ===================
    CBDEA
    ===================
    BGLxL
    the solution



















    SOLUTION
    1STSURDAYSUBJECTROOM #
    CKMONJ150
    BMTUEI250
    DN(xJ)WEDG100
    ELTHUH300=2xJ
    A(xJ)PFRIF200

    SOMETIMES IT'S EASIER TO USE CIRCLES
    WHEN THE QUESTION IS VAGUE!

    PROBLEM 4:
    Mr. A, B, C, D & E are exotic fish owners
      while their wives own a cat;
      each of which killed a fish on a weekend.

    Using the 2 clues below solve for each killer and prey.

    1. Mrs "A"'s cat killed the fish of the husband
        of the owner of the cat which killed "E"'s fish,
        while Mr "A"'s fish was killed by Mrs "B"'s cat.
    2. Mr "D"'s fish was killed by the cat
        owned by the wife of the man
        whose fish was killed by Mrs "C"'s cat.

    logicp4gif
    NOTE:
      Y=\B since A=\D
      Y=\A since B=\C
      THUS Y=E and X=C etc.
      ARROWS SHOW WICH CAT KILLED WHICH FISH
    PROBLEM 5:
    5 racing sloop owners A, B, C, D & E
      all have two daughters with the same
      but different initials.

    Using the 4 clues below solve for each owner,
      sloop, daughters and the winners
      aboard sloop "C".

    1. Each race sloop owner named his sloop
        after the daughter whose sister
        has the same initials as his own daughter
        - the 2 owners and their 4 daughters
          have 5 different initials.
    2. "E"'s daughters are "B" & "C".
    3. "C"'s sloop the "A" has a daughter "D".
    4. "B"owns sloop "E".

    NOTE:
      From 1:
      A typical arrangement for owner O of sloop Z,
      with daughters x & y, and
      a second owner S, with daughters y & z,
      is shown below, FIG. 1
    logicp51gif
    From 2:
      E, his car Z, and his 2 daughters c & b
      give 2 possibilities, as shown below.
    logicp523gif
    From 3:
      C who owns sloop A and has a daughter d,
      give 2 possibilities, as shown below.
    logicp545gif
    From adding FIG. 2 to FIG. 4:
      one gets the impossible solution
      with owner and daughter
      having the same initial, below.
    logicp56gif
    From adding FIG. 3 to FIG. 4 and
      adding B owns sloop E:
      one gets the solution, below.
    logicp57gif
    SOLUTION
    OWNERSLOOPSIBS
    ABE, C
    BED, A
    CAB, D
    DCA, E
    EDC, B
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