mscroggs.co.uk
mscroggs.co.uk

subscribe

Puzzles

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 this puzzle, check out Sunday Afternoon Maths LXIV,
puzzles about numbers, or a random puzzle.

Archive

Show me a random puzzle
 Most recent collections 

Advent calendar 2024

Advent calendar 2023

Advent calendar 2022

Advent calendar 2021


List of all puzzles

Tags

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

Archive

Show me a random puzzle
▼ show ▼
© Matthew Scroggs 2012–2025