Random Puzzles - BrainBashers

Puzzle 1

What number comes next in the sequence:

1 · 2 · 3 · 5 · 9 · 12 · ?

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Puzzle 2

Imagine a bottle recycling skip, empty other than one lonely bottle.

Every hour, on the hour, people come and put bottles into the skip.

The first hour, at noon, one person came and put a bottle in.

One hour later, two people each placed a bottle into the skip.

An hour later, four people each placed a bottle into the skip.

This doubling of people continued until 11pm, when the skip was finally full.

When was the skip exactly half full?

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Puzzle 3

The following sentence is true.

The previous sentence is false.

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Puzzle 4

Chess Contestall logic puzzles

At the local games evening, four friends were competing in the chess and croquet competitions.

Frankie beat Glen in chess, Dale came third, and the 16-year-old won.
Frankie came second in croquet, the 15-year-old won, Dale beat the 18-year-old, and the 19-year-old came third.
Emery is 3 years younger than Glen.
The person who came last in chess came third in croquet, and only one person got the same position in both games.
Can you find the ages of the people and their positions in the two games?

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Answer
Name    Age    Chess  Croquet
Dale    15     3      1
Emery   16     1      4
Frankie 18     2      2
Glen    19     4      3

Reasoning
The possible ages are: 15, 16, 18, 19.

Breaking the clues down, and numbering them:
Frankie beat Glen in chess. Dale came third (chess). The 16-year-old won (chess). Frankie came second in croquet. The 15-year-old won (croquet). Dale beat the 18-year-old (croquet). The 19-year-old came third (croquet). Emery is 3 years younger than Glen. The person who came last in chess came third in croquet. Only one person got the same position in both games.
By (4), Frankie came 2^nd in croquet.
Name    Age    Chess  Croquet
Dale
Emery
Frankie               2
Glen

By (2), Dale came 3^rd in chess.
Name    Age    Chess  Croquet
Dale           3
Emery
Frankie               2
Glen

By (8), Emery is 15 or 16, and Glen is 18 or 19.

By (9), the person who came 4^th in chess, came 3^rd in croquet, and by (7), they are 19. This can't be Dale (3^rd in chess), or Frankie (2^nd in croquet), or Emery (aged 15 or 16), so it must be Glen.
Name    Age    Chess  Croquet
Dale           3
Emery
Frankie               2
Glen    19     4      3

By (6), Dale can't have been 4^th in croquet, so must be 1^st. Leaving Emery in 4^th.
Name    Age    Chess  Croquet
Dale           3      1
Emery                 4
Frankie               2
Glen    19     4      3

By (10), only one person got the same position in both games, this can't be Emery 4^th in both (as Glen is already 4^th in chess), so must be Frank, 2^nd in both. Leaving Emery 1^st in chess.
Name    Age    Chess  Croquet
Dale           3      1
Emery          1      4
Frankie        2      2
Glen    19     4      3

By (3) and (5) we know the ages of the winners in each competition, and Frankie is therefore 18.
Name    Age    Chess  Croquet
Dale    15     3      1
Emery   16     1      4
Frankie 18     2      2
Glen    19     4      3