# Puzzles

## Archive

Show me a random puzzle**Most recent collections**

#### Sunday Afternoon Maths LXVII

Coloured weightsNot Roman numerals

#### Advent calendar 2018

#### Sunday Afternoon Maths LXVI

Cryptic crossnumber #2#### Sunday Afternoon Maths LXV

Cryptic crossnumber #1Breaking Chocolate

Square and cube endings

List of all puzzles

## Tags

prime numbers algebra proportion bases digits taxicab geometry speed polygons logic addition regular shapes floors 3d shapes factors parabolas balancing sequences shape books hexagons probability rectangles partitions 2d shapes angles ellipses symmetry area remainders circles crossnumbers square numbers sums differentiation wordplay trigonometry integration triangle numbers graphs coordinates star numbers surds lines scales square roots ave volume squares probabilty geometry chocolate dates perfect numbers indices percentages arrows means cards games people maths grids sum to infinity sport unit fractions division multiplication rugby chalkdust crossnumber perimeter factorials numbers colouring dodecagons number menace averages pascal's triangle cube numbers doubling triangles functions irreducible numbers spheres integers quadratics cryptic clues money coins crosswords cryptic crossnumbers calculus fractions advent christmas clocks dice planes folding tube maps chess time complex numbers routes palindromes multiples odd numbers mean shapes## More doubling cribbage

Source: Inspired by Math Puzzle of the Week blog

Brendan and Adam are playing lots more games of high stakes cribbage: whoever
loses each game must double the other players money. For example, if Brendan has £3 and Adam has £4 then Brendan wins, they will have £6
and £1 respectively.

In each game, the player who has the least money wins.

Brendan and Adam notice that for some amounts of
starting money, the games end with one player having all the money; but for other amounts, the games continue forever.

For which
amounts of starting money will the games end with one player having all the money?

## Doubling cribbage

Source: Math Puzzle of the Week blog

Brendan and Adam are playing high stakes cribbage: whoever loses each game must double the other players money. For example, if Brendan has £3 and Adam has £4 then Brendan wins, they will have £6 and £1 respectively.

Adam wins the first game then loses the second game. They then notice that they each have £180. How much did each player start with?