2 December

Today's number is the area of the largest dodecagon that it's possible to fit inside a circle with area \(\displaystyle\frac{172\pi}3\).

Show answer

Cube multiples

Six different (strictly) positive integers are written on the faces of a cube. The sum of the numbers on any two adjacent faces is a multiple of 6.
What is the smallest possible sum of the six numbers?

Show answer & extension


Draw a regular polygon. Connect all its vertices to every other vertex. For example, if you picked a pentagon or a hexagon, the result would look as follows:
Colour the regions of your shape so that no two regions which share an edge are the same colour. (Regions which only meet at one point can be the same colour.)
What is the least number of colours which this can be done with?

Show answer & extension


Show me a random puzzle
 Most recent collections 

Sunday Afternoon Maths LXVII

Coloured weights
Not Roman numerals

Advent calendar 2018

Sunday Afternoon Maths LXVI

Cryptic crossnumber #2

Sunday Afternoon Maths LXV

Cryptic crossnumber #1
Breaking Chocolate
Square and cube endings

List of all puzzles


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


Show me a random puzzle
▼ show ▼
© Matthew Scroggs 2019