# 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

calculus spheres geometry games folding tube maps differentiation division dodecagons partitions triangles floors chess digits shape clocks area sums integers logic multiples algebra probabilty complex numbers square numbers bases perimeter money sequences percentages volume chalkdust crossnumber advent prime numbers mean pascal's triangle triangle numbers crosswords factorials surds dates books unit fractions wordplay addition irreducible numbers perfect numbers averages number circles taxicab geometry arrows speed graphs ave indices angles dice grids lines ellipses balancing rectangles symmetry people maths cube numbers scales star numbers palindromes functions proportion trigonometry doubling menace parabolas fractions chocolate coins multiplication 2d shapes cryptic clues means sport cards remainders 3d shapes coordinates shapes integration factors probability square roots time rugby numbers cryptic crossnumbers squares planes odd numbers routes colouring sum to infinity christmas polygons hexagons crossnumbers regular shapes quadratics## 21 December

Today's number is a multiple of three. The average (mean) of all the answers that are multiples of three is a multiple of 193.