Equal lengths

The picture below shows two copies of the same rectangle with red and blue lines. The blue line visits the midpoint of the opposite side. The lengths shown in red and blue are of equal length.
What is the ratio of the sides of the rectangle?

Show answer

1 December

What is area of the largest area rectangle which will fit in a circle of radius 10?

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


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


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