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Comments in green were written by me. Comments in blue were not written by me.
2024-12-19
Matt, great card this year! Problems 1 and 2 are slightly ambiguous though in that you did not specify that each digit could only be used once.
I initially thought the answers were simply 44×44 = 1936 and 99×99999999 = 9899999901, respectively ????
Dan Whitman
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Is MEDUSA the new BODMAS?
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Tube map kaleidocycles
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Solving the cross diagonal cover problem
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Braiding, pt. 2
Braiding, pt. 1
Making names in Life
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Euro 2016 stickers
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Proving Pythagoras' theorem
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Mathematical Games
of Martin Gardner
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How to kick a conversion
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Optimal Pac-Man
Tube map stellated rhombicuboctahedron
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Tennis maths
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Assorted christmaths
Pointless probability
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"Uncanny" royal coincidence
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Tube map Platonic solids, pt. 2
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inverse matrices
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fonts
fence posts
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game of life
propositional calculus
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hats
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interpolation
pizza cutting
machine learning
programming
tennis
numbers
royal baby
london
bodmas
probability
light
finite group
signorini conditions
python
squares
tmip
folding paper
braiding
weak imposition
simultaneous equations
flexagons
trigonometry
realhats
the aperiodical
zines
kings
ucl
pac-man
bots
approximation
countdown
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matrix multiplication
boundary element methods
logs
hexapawn
phd
frobel
gather town
newcastle
guest posts
runge's phenomenon
triangles
curvature
graphs
errors
oeis
folding tube maps
speed
books
reddit
stickers
determinants
quadrilaterals
mean
php
geometry
javascript
christmas card
mathsteroids
estimation
sorting
bubble bobble
data
misleading statistics
datasaurus dozen
databet
live stream
puzzles
binary
coins
menace
logo
rhombicuboctahedron
cross stitch
big internet math-off
manchester science festival
matrices
game show probability
wool
pi
matt parker
latex
regular expressions
sobolev spaces
electromagnetic field
sport
gaussian elimination
martin gardner
manchester
matrix of minors
palindromes
pascal's triangle
fractals
dragon curves
computational complexity
a gamut of games
pythagoras
chess
friendly squares
statistics
numerical analysis
european cup
crosswords
logic
hannah fry
convergence
map projections
christmas
mathsjam
dataset
go
golden ratio
crochet
national lottery
cambridge
craft
accuracy
matrix of cofactors
draughts
radio 4
asteroids
sound
dinosaurs
graph theory
dates
noughts and crosses
pi approximation day
bempp
weather station
plastic ratio
error bars
standard deviation
anscombe's quartet
wave scattering
chalkdust magazine
golden spiral
exponential growth
edinburgh
24 hour maths
turtles
royal institution
inline code
mathslogicbot
harriss spiral
reuleaux polygons
polynomials
youtube
finite element method
rugby
captain scarlet
crossnumbers
recursion
video games
geogebra
advent calendar
final fantasy
talking maths in public
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preconditioning
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ternary
stirling numbers
people maths
arithmetic
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© Matthew Scroggs 2012–2025
I initially thought the answers were simply 44×44 = 1936 and 99×99999999 = 9899999901, respectively ????
on /blog/112