mscroggs.co.uk
mscroggs.co.uk

subscribe

Blog

Christmas card 2018

 2018-12-08 
Just like last year and the year before, TD and I spent some time in November this year designing a Chalkdust puzzle Christmas card.
The card looks boring at first glance, but contains 10 puzzles. By splitting the answers into pairs of digits, then drawing lines between the dots on the cover for each pair of digits (eg if an answer is 201304, draw a line from dot 20 to dot 13 and another line from dot 13 to dot 4), you will reveal a Christmas themed picture. Colouring the region of the card labelled R red or orange will make this picture even nicer.
If you want to try the card yourself, you can download this pdf. Alternatively, you can find the puzzles below and type the answers in the boxes. The answers will be automatically be split into pairs of digits, lines will be drawn between the pairs, and the red region will be coloured...
If you enjoy these puzzles, then you'll almost certainly enjoy this year's puzzle Advent calendar.
                        
(Click on one of these icons to react to this blog post)

You might also enjoy...

Comments

Comments in green were written by me. Comments in blue were not written by me.
Someone told me I would like this puzzle and they were right!
Blaine
×1                 Reply
@Carmel: It's not meant to check your answers. It only shows up red if the number you enter cannot be split into valid pairs (eg the number has an odd number of digits or one of the pairs of digits is greater than 20).
Matthew
                 Reply
The script for checking the answers doesn't work properly
Carmel
                 Reply
Thank you Shawn!
SueM
                 Reply
So satisfying!
Heather
×1                 Reply
Great puzzle problems! Hint on #9: try starting with an analogous problem using smaller numbers (e.g. 3a + 10b). This helped me to see what I had to do more generally.
Noah
   ×1              Reply
 Add a Comment 


I will only use your email address to reply to your comment (if a reply is needed).

Allowed HTML tags: <br> <a> <small> <b> <i> <s> <sup> <sub> <u> <spoiler> <ul> <ol> <li> <logo>
To prove you are not a spam bot, please type "rotcaf" backwards in the box below (case sensitive):

Archive

Show me a random blog post
 2025 

Jan 2025

Christmas (2024) is over
Friendly squares
 2024 
▼ show ▼
 2023 
▼ show ▼
 2022 
▼ show ▼
 2021 
▼ show ▼
 2020 
▼ show ▼
 2019 
▼ show ▼
 2018 
▼ show ▼
 2017 
▼ show ▼
 2016 
▼ show ▼
 2015 
▼ show ▼
 2014 
▼ show ▼
 2013 
▼ show ▼
 2012 
▼ show ▼

Tags

talking maths in public a gamut of games polynomials geometry advent calendar stirling numbers latex map projections captain scarlet hexapawn stickers christmas card rugby logs games manchester science festival pizza cutting weak imposition video games tmip european cup edinburgh bots runge's phenomenon noughts and crosses people maths error bars draughts game of life world cup matrix multiplication reddit newcastle asteroids ucl trigonometry arithmetic turtles pascal's triangle golden spiral approximation matrices dragon curves wool oeis datasaurus dozen mathsteroids realhats martin gardner platonic solids sport books signorini conditions convergence python curvature errors the aperiodical bodmas bempp speed game show probability graph theory golden ratio sorting preconditioning final fantasy fonts london pac-man sound folding paper hannah fry mean ternary simultaneous equations mathsjam christmas geogebra exponential growth phd gerry anderson standard deviation probability machine learning finite group zines palindromes cambridge dinosaurs youtube weather station javascript 24 hour maths logic determinants manchester numerical analysis harriss spiral databet rhombicuboctahedron data matrix of cofactors gather town reuleaux polygons pi royal institution quadrilaterals boundary element methods electromagnetic field mathslogicbot finite element method interpolation pythagoras wave scattering braiding nine men's morris flexagons graphs folding tube maps cross stitch countdown numbers accuracy programming crochet anscombe's quartet football matrix of minors frobel live stream national lottery london underground triangles inverse matrices binary guest posts craft go news dataset squares data visualisation friendly squares radio 4 coins fractals correlation tennis big internet math-off chess logo misleading statistics bubble bobble menace matt parker computational complexity propositional calculus light php chebyshev sobolev spaces regular expressions kings dates inline code puzzles hyperbolic surfaces statistics royal baby chalkdust magazine raspberry pi recursion pi approximation day estimation gaussian elimination plastic ratio crossnumber fence posts hats

Archive

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