Sunday Afternoon Maths LXIV

 Posted on 2018-05-06 

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

Digitless factor

Ted thinks of a three-digit number. He removes one of its digits to make a two-digit number.
Ted notices that his three-digit number is exactly 37 times his two-digit number. What was Ted's three-digit number?

Show answer & extension

Backwards fours

If A, B, C, D and E are all unique digits, what values would work with the following equation?
$$ABCCDE\times 4 = EDCCBA$$

Show answer

If you enjoyed these puzzles, check out Advent calendar 2019,
puzzles about lines, or a random puzzle.


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


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


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