Advent calendar 2019

19 December

The diagram below shows three squares and five circles. The four smaller circles are all the same size, and the red square's vertices are the centres of these circles.
The area of the blue square is 14 units. What is the area of the red square?

Show answer


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


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


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