mscroggs.co.uk
mscroggs.co.uk

subscribe

Blog

Christmas card 2019

 2019-12-08 
Just like last year, the year before 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 9 puzzles. By splitting the answers into two digit numbers, then drawing lines labelled with each number (eg if an answer is 201304, draw the lines labelled 20, 13 and 4), you will reveal a Christmas themed picture. Colouring the regions of the card containing circles red, the regions containing squares green, and the regions containing stars white or yellow 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 two digit numbers, the lines will be drawn, and the regions will be coloured...

Similar posts

Christmas card 2018
Christmas card 2017
Christmas card 2016
Christmas (2019) is over

Comments

Comments in green were written by me. Comments in blue were not written by me.
Rishabh, what do you see that I do not?
Rob Glencairn
                 Reply
Thanks for the feedback. (I now understand the need for redaction). My son sent me your link as a Xmas present. I must think of an appropriate retaliation. (What is a PDF?)Think I've fixed 1,6 and 9....8 eludes me, for the moment.
Rob
                 Reply
@Rob: It looks to me like you've made mistakes in questions 1, 6, 8, and 9. The hints from the back of the pdf might help:

1. How many numbers between 1 and 10,000 have 1 as their final digit? How many have 1 as their penultimate digit?

6. How many ways can you write 1? 2? 3? 4? 5? What's the pattern?

8. How many zeros does 10! end in? How many zeros does 20! end in? How many zeros does 30! end in?

9. Carol’s sum is odd. What does this tell you about the 5- and 6-digit numbers?
Matthew
×1   ×1   ×2   ×1   ×1     Reply
I'm 71, with one good eye left. What am I missing?
1. 400001
2. 1849
3. 2002
4. 130405
5. 120306
6. 53?
7. 171175
8. 59?
9. 313525
Rob
                 Reply
It was fun.
Rishabh
   ×1         ×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>
To prove you are not a spam bot, please type "graph" in the box below (case sensitive):

Archive

Show me a random blog post
 2020 

Jul 2020

Happy τ+e-6 Approximation Day!

May 2020

A surprising fact about quadrilaterals
Interesting tautologies

Mar 2020

Log-scaled axes

Feb 2020

PhD thesis, chapter ∞
PhD thesis, chapter 5
PhD thesis, chapter 4
PhD thesis, chapter 3
Inverting a matrix
PhD thesis, chapter 2

Jan 2020

PhD thesis, chapter 1
Gaussian elimination
Matrix multiplication
Christmas (2019) is over
 2019 
▼ show ▼
 2018 
▼ show ▼
 2017 
▼ show ▼
 2016 
▼ show ▼
 2015 
▼ show ▼
 2014 
▼ show ▼
 2013 
▼ show ▼
 2012 
▼ show ▼

Tags

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

Archive

Show me a random blog post
▼ show ▼
© Matthew Scroggs 2012–2020