mscroggs.co.uk
mscroggs.co.uk

subscribe

Puzzles

21 December

This year, I posted instructions for making a dodecahedron and a stellated rhombicuboctahedron.
To get today's number, multiply the number of modules needed to make a dodecahedron by half the number of tube maps used to make a stellated rhombicuboctahedron.

Show answer

Folding tube maps

Back in 2012, I posted instructions for folding a tetrahedron from tube maps. When tube maps are used, the sides of the tetrahedron are not quite equal. What ratio would the rectangular maps need to be in to give a regular tetrahedron?

Show answer & extension

Archive

Show me a random puzzle
 Most recent collections 

Advent calendar 2019

Sunday Afternoon Maths LXVII

Coloured weights
Not Roman numerals

Advent calendar 2018

Sunday Afternoon Maths LXVI

Cryptic crossnumber #2

List of all puzzles

Tags

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

Archive

Show me a random puzzle
▼ show ▼
© Matthew Scroggs 2012–2020