mscroggs.co.uk
mscroggs.co.uk

subscribe

Puzzles

Multiples of three

If the digits of a number add up to a multiple of three, then the number is a multiple of three. Therefore if a two digit number, \(AB\) (first digit \(A\), second digit \(B\); not \(A\times B\)), is a multiple of three, then \(A0B\) is also a multiple of three.
If \(AB\div 3=n\), then what is \(A0B\div 3\)?

Show answer & extension

Tags: numbers
If you enjoyed this puzzle, check out Sunday Afternoon Maths XIX,
puzzles about numbers, or a random puzzle.

Archive

Show me a random puzzle
 Most recent collections 

Advent calendar 2025

Advent calendar 2024

Advent calendar 2023

Advent calendar 2022


List of all puzzles

Tags

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

Archive

Show me a random puzzle
▼ show ▼
© Matthew Scroggs 2012–2026