# 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

shapes routes colouring arrows regular shapes coordinates speed cryptic clues partitions percentages squares polygons number sums money taxicab geometry probabilty wordplay doubling complex numbers bases ave quadratics crossnumbers integers chocolate cards menace rugby square roots people maths cryptic crossnumbers cube numbers chess lines factorials perfect numbers averages prime numbers geometry division rectangles shape addition dice proportion means time probability surds graphs odd numbers triangles chalkdust crossnumber integration hexagons dates palindromes mean numbers dodecagons unit fractions circles sport folding tube maps pascal's triangle sum to infinity balancing square numbers 3d shapes trigonometry remainders multiplication indices 2d shapes algebra perimeter games digits area ellipses factors sequences irreducible numbers volume planes floors angles calculus scales books multiples spheres clocks symmetry star numbers advent christmas logic fractions functions differentiation triangle numbers crosswords coins grids parabolas## 22 December

Today's number is a palindrome. Today's number is also the number of palindromes between 111 and 11111 (including 111 and 11111).

## 14 December

What is the only palindromic three digit prime number which is also palindromic when written in binary?