# 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

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

22 is two times an odd number. Today's number is the mean of all the answers on days (including today) that are two times an odd number.

Clarification: You are taking the mean for answers on days that are two times an odd numbers; ie. the days are two times odd, not the answers.

## 16 December

Today's number is four thirds of the average (mean) of the answers for 13th, 14th, 15th and 16th December.