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

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

Archive

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