mscroggs.co.uk
mscroggs.co.uk
Click here to win prizes by solving the mscroggs.co.uk puzzle Advent calendar.
Click here to win prizes by solving the mscroggs.co.uk puzzle Advent calendar.

subscribe

Advent calendar 2017

20 December

What is the largest number that cannot be written in the form \(10a+27b\), where \(a\) and \(b\) are nonnegative integers (ie \(a\) and \(b\) can be 0, 1, 2, 3, ...)?

Show answer & extension

Archive

Show me a random puzzle
 Most recent collections 

Sunday Afternoon Maths LXVII

Coloured weights
Not Roman numerals

Advent calendar 2018

Sunday Afternoon Maths LXVI

Cryptic crossnumber #2

Sunday Afternoon Maths LXV

Cryptic crossnumber #1
Breaking Chocolate
Square and cube endings

List of all puzzles

Tags

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

Archive

Show me a random puzzle
▼ show ▼
© Matthew Scroggs 2012–2019