# 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

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

If two people stand 1km apart and walk in the same direction, how far will the have to walk until they collide due to the curvature of the Earth? (diameter of Earth = 12,742km)