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 Quarter the Cross
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Category Archives: Fun
Quarter the Cross: An Elegant Construction
Last month, I presented an infinite pattern of nested crosses as a response to the #QuarterTheCross challenge on Twitter. The idea is to find interesting ways to shade onequarter of the area of the cross built from five squares.Now David Butler, a math lecturer … Continue reading
Quarter the Cross
Yesterday, I noticed that some of the math teachers I follow on Twitter were challenging their students, and themselves, with the #quarterthecross problem. The problem is simply to find interesting regions of a fivesquare cross that take up exactly onequarter of … Continue reading
Spaghetti Puzzle #1
About a month ago, math educator Marilyn Burns tweeted this puzzle: Here's a problem I've thought about for a long time. Not making progress, but I'm still fascinated. Help? pic.twitter.com/r6iagNUn76 — Marilyn Burns (@mburnsmath) December 6, 2015 Spoiler Alert: … Continue reading
Posted in Fun, Puzzles
Tagged Calculus, Ivan Moscovich, Probability, Spaghetti Puzzle, Walking Stick Puzzle
6 Comments
A Mathematical Family Tree
I am delighted by what I just learned about my mathematical family tree. It started with this tweet by scientist and writer Paul Halpern: More than 120,000 mathematicians can trace their scholarly heritage back to Byzantine thinker Manuel Bryennios: http://t.co/ejlzX2AO3K … Continue reading
Posted in Fun, Math
Tagged H.S.M. Coxeter, Mathematics Genealogy Project, Nicolo Tartaglia, Roger Penrose, William Shaw
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Puzzle #9 (Followup): Melting Fractals
The song “Let it Go” from the movie Frozen celebrates “frozen fractals.” I suppose a frozen fractal is something like the Koch snowflake. Lately, though, one of my puzzles has made me more interested in melting fractals. The challenge of Puzzle … Continue reading
Posted in Fun, Graphic Presentation, Math, Puzzles, Visualization
Tagged Big Data, Fractals, Latin Hypercube Sampling, Latin Squares, MATLAB, Sierpinski Tetrahedron
2 Comments
Puzzle #7 (Followup): Treasury Island, Part 1
In Puzzle #7: The Mysterious Islands, I told the story of two islands where each individual’s remaining lifespan can be perfectly predicted. The lifespans on Uniformia are evenly distributed, and their average remaining life expectancy will gradually decline over time. … Continue reading
Posted in Bonds, Fun, Math, Puzzles
Tagged Life Expectancy, Puzzle, Weighted Average Life
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