# Puzzles

## Archive

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#### 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

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

I have three packs of playing cards with identical backs. Call the packs A, B and C.

I draw a random card from pack A and shuffle it into pack B.

I now turn up the top card of pack A, revealing the Queen of Hearts.

Next, I draw a card at random from pack B and shuffle it into pack C. Then, I turn up the top card of pack B, revealing another Queen of Hearts.

I now draw a random card from pack C and place it at the bottom of pack A.

What is the probability that the card at the top of pack C is the Ace of Spades?

## Whist

Messrs. Banker, Dentist, Apothecary and Scrivener played whist last night. (whist is a four player card game where partners sit opposite each other.) Each of these gentlemen is the namesake of another's vocation.

Last night, the apothecary partnered Mr. Apothecary; Mr. Banker's partner was the scrivener; on Mr. Scrivener's right sat the dentist.

Who sat on the banker's left?