The Grey Labyrinth is a collection of puzzles, riddles, mind games, paradoxes and other intellectually challenging diversions. Related topics: puzzle games, logic puzzles, lateral thinking puzzles, philosophy, mind benders, brain teasers, word problems, conundrums, 3d puzzles, spatial reasoning, intelligence tests, mathematical diversions, paradoxes, physics problems, reasoning, math, science.

   

Christmas Confusion

First, we simplify and number the statements.

A1: water colours to Chester
A2: ribbon to Alice
A3: model train from Deirdre
A4: diary from Alice
A5: diary and pocket watch to Deirdre
A6: loudspeakers from Chester to Bruno
A7: textbook from Bruno
A8: pocket knife not from Chester
B1: DVD player to Alice
B2: textbook to Chester
B3: diary and chocolates to Bruno
B4: chocolates from Alice
B5: socks from Bruno
B6: DVD player from Bruno
B7: model train from Bruno
B8: mittens from Alice to Bruno
C1: pocket watch to Bruno
C2: ribbon to Bruno
C3: DVD player from Chester
C4: pocket watch from Alice
C5: ribbon from Chester
C6: diary from Chester
C7: textbook from Chester
C8: pocket knife from Chester to Deirdre
D1: socks to Alice
D2: loudspeakers to Bruno
D3: DVD player to Deirdre
D4: model train to Bruno
D5: water colours from Deirdre to Chester
D6: chocolates to Chester
D7: pocket watch to Chester
D8: textbook and ribbon to Alice

Figuring out which family member is always correct would be helpful. C3, C5, C6, C7 and C8 together claim that Chester gave five gifts. Since each family member only gave one gift to each of the other family members, Chester is not always correct.
B3 and B4 mean that Alice gave Bruno the box of chocolates, but B8 says her gift to him was the mittens. So Bruno is not always correct.

Let's assume Deirdre is always correct. This gives us the following:

AliceBrunoChesterDeirdre
Alice------
Bruno------
Chester------
DeirdreWater colours------
SocksLoudspeakers Chocolates DVD player
Textbook Model train Pocket watch
Ribbon

TA1: water colours to Chester
TA2: ribbon to Alice
A3: model train from Deirdre
A4: diary from Alice
FA5: diary and pocket watch to Deirdre
A6: loudspeakers from Chester to Bruno
A7: textbook from Bruno
A8: pocket knife not from Chester
FB1: DVD player to Alice
FB2: textbook to Chester
FB3: diary and chocolates to Bruno
B4: chocolates from Alice
B5: socks from Bruno
B6: DVD player from Bruno
FB7: model train from Bruno
B8: mittens from Alice to Bruno
FC1: pocket watch to Bruno
FC2: ribbon to Bruno
C4: pocket watch from Alice
C6: diary from Chester
At least one of C3 and C8 is false:
C3: DVD player from Chester
C8: pocket knife from Chester to Deirdre
At least one of C5 and C7 is false:
C5: ribbon from Chester
C7: textbook from Chester
TD1: socks to Alice
TD2: loudspeakers to Bruno
TD3: DVD player to Deirdre
TD4: model train to Bruno
TD5: water colours from Deirdre to Chester
TD6: chocolates to Chester
TD7: pocket watch to Chester
TD8: textbook and ribbon to Alice

No contradictions so far. We can concude that Alice has to be the 3/4 correct family member, since Bruno and Chester both have four false statements each. Let's add another assumption: That Bruno is right half the time. That means that B4, B5, B6 and B8 have to be true. B5 means that A7 has to be false (or Bruno gave Alice two presents). Since we now know Alice's two false statements, the remaining one's have to be true.
A4 and A8 mean that C6 and C8 are false. B6 means that C3 is false. B4 means that C4 is false (else Alice gave Chester two presents). But since one of C5 and C7 have to be false (else Chester gives Alice two presents), Chester has at most one true statement, which is less than one quarter.
That's a contradiction, so if Deirdre is always correct, Bruno is only correct one quarter of the time and Chester is correct half the time. Moving back to before we assumed Bruno to be correct half the time, this means that C4 and C6 are true. C6 means that A4 is false, which once again leads us into the situation of knowing that Alice's remaining statements are true. C4 means that B4 is false, A7 means that B5 is false. A8 means that C8 is false so C3 is true, which means that B6 is false. So Bruno has seven false statements, so the assumption that Deirdre is always correct must be false. Therefore, Alice is the one that is always correct.

Jumping back to the very beginning, this gives us the following:

Alice Bruno Chester Deirdre
Alice ------Diary
Bruno ------Textbook
Chester Loudspeakers ------
Deirdre ------Model train
Ribbon Water colours Pocket watch

TA1: water colours to Chester
TA2: ribbon to Alice
TA3: model train from Deirdre
TA4: diary from Alice
TA5: diary and pocket watch to Deirdre
TA6: loudspeakers from Chester to Bruno
TA7: textbook from Bruno
TA8: pocket knife not from Chester
B1: DVD player to Alice
B2: textbook to Chester
FB3: diary and chocolates to Bruno
B4: chocolates from Alice
B5: socks from Bruno
B6: DVD player from Bruno
FB7: model train from Bruno
B8: mittens from Alice to Bruno
FC1: pocket watch to Bruno
FC2: ribbon to Bruno
C3: DVD player from Chester
FC4: pocket watch from Alice
C5: ribbon from Chester
FC6: diary from Chester
FC7: textbook from Chester
FC8: pocket knife from Chester to Deirdre
D1: socks to Alice
TD2: loudspeakers to Bruno
D3: DVD player to Deirdre
D4: model train to Bruno
D5: water colours from Deirdre to Chester
D6: chocolates to Chester
FD7: pocket watch to Chester
D8: textbook and ribbon to Alice

Since Chester has six false statements, the remaining two must be true. So the silk ribbon is from Chester to Alice, and the DVD player is from Chester to Deirdre (since he gave Alice the ribbon and Bruno the loudspeakers). Therefore, B1 and B6 are false, and this gives Bruno four false statements, telling us that B2, B4, B5 and B8 are true.
This gives us:

Alice Bruno Chester Deirdre
Alice ------MittensDiaryChocolates
Bruno ------TextbookSocks
Chester Ribbon Loudspeakers ------DVD player
Deirdre ------Model train
Water colours Pocket watch

TA1: water colours to Chester
TA2: ribbon to Alice
TA3: model train from Deirdre
TA4: diary from Alice
TA5: diary and pocket watch to Deirdre
TA6: loudspeakers from Chester to Bruno
TA7: textbook from Bruno
TA8: pocket knife not from Chester
FB1: DVD player to Alice
TB2: textbook to Chester
FB3: diary and chocolates to Bruno
TB4: chocolates from Alice
TB5: socks from Bruno
FB6: DVD player from Bruno
FB7: model train from Bruno
TB8: mittens from Alice to Bruno
FC1: pocket watch to Bruno
FC2: ribbon to Bruno
TC3: DVD player from Chester
FC4: pocket watch from Alice
TC5: ribbon from Chester
FC6: diary from Chester
FC7: textbook from Chester
FC8: pocket knife from Chester to Deirdre
D1: socks to Alice
TD2: loudspeakers to Bruno
D3: DVD player to Deirdre
D4: model train to Bruno
D5: water colours from Deirdre to Chester
D6: chocolates to Chester
FD7: pocket watch to Chester
FD8: textbook and ribbon to Alice

As can be seen from the table, the pocket watch is from Bruno, the socks are Alice's, the box of chocolates belongs to Chester and the water colours are from Deirdre. Also, since D7 and D8 are both false, D4 has to be true, leaving only one spot for the pocket knife; from Deirdre to Alice.

2.92 stars. Votes are updated daily.


On a scale of 1 to 5, 1 being among your least favorite, 5 being among your most favorite, how would you rate this puzzle?

1 2 3 4 5

Copyright © 1996-2017 Wx3, All Rights Reserved.