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A Mathematical Mystery Tour: 10 Mathematical Wonders and Oddities. Ed Dickey. All aboard… … for Reasoning and Sense Making, with a smile. Martin Gardner. Dedicated to Martin Gardner whose birthday was yesterday (October 21, 1914) and who passed away on May 22, 2010.
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A Mathematical Mystery Tour: 10 Mathematical Wonders and Oddities Ed Dickey College of Education Instruction &Teacher Education
All aboard… … for Reasoning and Sense Making, with a smile. SCCTM
Martin Gardner • Dedicated to Martin Gardner whose birthday was yesterday (October 21, 1914) and who passed away on May 22, 2010. • G4G Celebrations Worldwide SCCTM
10 Wonders and Oddities • Magic Squares (MG inspired) • Mobius Strip & Klein Bottle • Monty’s Dilemma • Buffon’s Needle Problem • Curry’s Paradox (MG inspired) • The Birthday Problem • Kissing Numbers & Packing Spheres • Symmetry: Escher & Scott Kim (MG inspired) • Tower of Hanoi • Palindromes (MG inspired) SCCTM
1. Magic Squares • What is it? • “set of integers in serial order, beginning with 1, arranged in square formation so that the total of each row, column, and main diagonal are the same.” SCCTM
1. Magic Squares • The “order” of a magic square is the number of cells on one its sides • Order 2? (none) • Order 3? (one, counting symmetry only once) • Order 4? (880) SCCTM
1. Magic Squares • In 1514, Albrecht Dürer created an engraving named Melancholia that included a magic square. • In the bottom row of his 4 X 4 magic square you can see that he placed the numbers "15" and "14" side by side to reveal the date of his engraving. SCCTM
1. Magic Squares • Diabolical Magic Square • “… a magic square that remains magic if a row is shifted from top to bottom or bottom to top, and if a column is moved from one side to the other. SCCTM
1. Magic Squares • Temple Expiatori de la Sagrada Familia created by Antoni Gaudi (1852-1926) in Barcelona, Spain • Open to public but expected to be complete in 2026 SCCTM
1. Magic Squares SCCTM
1. Magic Squares Age of Jesus at the time of the Passion? SCCTM
1. Magic Squares • Applets for generating Magic Squares • http://www.allmath.com/magicsquare.php SCCTM
2. Mobius Strip and Klein Bottle • Mobius Strip • August Ferdinand Möbius • (1790 –1868) SCCTM
2. Mobius Strip and Klein Bottle • Recycling • Some properties of the Mobius Strip SCCTM
2. Mobius Strip and Klein Bottle • Klein Bottle • Felix Christian Klein (1849 –1925) SCCTM
2. Mobius Strip and Klein Bottle • A better view of the Klein Bottle • Buy one at the Acme Klein Bottle Company SCCTM
3. Monty’s Dilemma • In search of a new car, the player picks a door, say 1. • The game host then opens one of the other doors, say 3, to reveal a goat and offers to let the player pick door 2 instead of door 1. SCCTM
3. Monty’s Dilemma • Marilyn vos Savant “Ask Marilyn” in Parade magazine 1990. • “World’s highest IQ” 228 • Mrs. Robert Jarvik SCCTM
3. Monty’s Dilemma • As posed on the CBS Show NUMB3RS SCCTM
3. Monty’s Dilemma • NCTM Illuminations Site Lesson • http://illuminations.nctm.org/LessonDetail.aspx?id=L377 SCCTM
3. Monty’s Dilemma • Facebook? SCCTM
4. Buffon’s Needle Problem • Drop a need on a lined sheet of paper • What is the probability of the needle crossing one of the lines? • Probability related to p • Simulation of the probability lets you approximate p SCCTM
4. Buffon’s Needle Problem • George-Louis Leclerc, Comte de Buffon (1707 – 1788) SCCTM
4. Buffon’s Needle Problem • Java Applet Simulation • http://mste.illinois.edu/reese/buffon/bufjava.html • Video from Wolfram SCCTM
5. Curry’s or Hooper’s Paradox • In one case as two triangles, but with a 5×3 rectangle of area 15. • In the other case, same two triangles, but with an 8×2 rectangle of area 16. • How? SCCTM
5. Curry’s or Hooper’s Paradox • A right triangle with legs 13 and 5 can be cut into two triangles (legs 8, 3 and 5, 2, respectively). • The small triangles could be fitted into the angles of the given triangle in two different ways. SCCTM
5. Curry’s or Hooper’s Paradox • Applet to simulate • 13 x 5 • 8 x 3 • 5 x 2 SCCTM
5. Curry’s or Hooper’s Paradox • Illusion! • Of a Linear Hypotenuse in the 2nd Triangle SCCTM
6. The Birthday Problem • What is the probability that in a group of people, some pair have the SAME BIRTHDAY? • If there are 367 people (or more), the probability is 100% • COUNTERINTUITIVE! • With a group of 57 people the probability is 99% • It’s “50-50” with just 23 people. SCCTM
6. The Birthday Problem • Let P(A) be the probability of at least two people in a group having the same birthday and A’, the complement of A. • P(A) = 1 – P(A’) • What is P(A’)? • Probability of NO two people in a group having the same birthday. SCCTM
6. The Birthday Problem • In a group of 2, 3 more more, what it probability that the birthdays will be different? • (Let’s ignore Feb 29 for now.) • Person #2 has 364 possible birthdays so • The probability is 365/365 x 364/365 • Person #3 has 363 possible birthdays, so as not to match person #1 and #2 • The probability is 365/365 x 364/365 x 363/365 SCCTM
6. The Birthday Problem • Get the pattern for n people? • And P(A) is • How about a picture: SCCTM
6. The Birthday Problem • A Table? SCCTM
6. The Birthday Problem SCCTM
6. The Birthday Problem • NCTM Illuminations Birthday Paradox • http://illuminations.nctm.org/LessonDetail.aspx?id=L299 SCCTM
6. The Birthday Problem • Random: people and equally distributed birthdays • 2 US Presidents have the name birthday • Polk (11th) and Harding (29th) November 2 • 67 actresses won a Best Actress Oscar • Only 3 pairs share the same birthdays • Jane Wyman and Diane Keaton (January 5), Joanne Woodward and Elizabeth Taylor (February 27) and Barbra Streisand and Shirley MacLaine (April 24) SCCTM
6. The Birthday Problem • Birthdays are NOT evenly distributed. • In Northern Hemisphere summer sees more births. • In the US, more children conceived around the holidays of Christmas and New Years. • In Sweden 9.3% of the population is born in March and 7.3% in November when a uniform distribution would give 8.3% SCCTM
6. The Birthday Problem • How about with this group? • Here are 15 birthdays of people mentioned this presentation. • Can we get a match? OPEN SCCTM
7. Kissing Numbers and Packing Spheres • What is the largest number identical spheres that can be packed into a fixed space? • In two-dimensions, the sphere packing problem involves packing circles. This problem can be modeled with coins or plastic disks and is solvable by high school students. SCCTM
7. Kissing Numbers and Packing Spheres • In 1694, Isaac Newton and David Gregory argued about the 3D kissing number. • 12 or 13? • Proof that 12 is the maximum (“all physicists know and most mathematicians believe…”) was not accepted until 1953 SCCTM
7. Kissing Numbers and Packing Spheres • Kissing Number problem from Martin Gardner • Rearrange the triangle of six coins into a hexagon, • By moving one coin at a time, so that each coin moved is always touching at least two others SCCTM
7. Kissing Numbers and Packing Spheres • Problems of 4, 5, and n-dimension sphere packing have application in radio transmissions (cell phone signals) across different frequency spectrum. • Kenneth Stephenson tells the Mathematical Tale in the Notices of the AMS. SCCTM
7. Kissing Numbers and Packing Spheres • “It is an article of mathematical faith that every topic will find connections to the wider world—eventually. • For some, that isn’t enough. For some it is real-time exchange between the mathematics and the applications that is the measure of a topic.” SCCTM
8. Symmetry: M.C. Escher & Scott Kim • M.C. Escher (1898-1972) • Produced mathematically inspired woodcuts and lithographs • Many including concepts of symmetry, infinity, and tessellations SCCTM
8. Symmetry: M.C. Escher & Scott Kim • Symmetry SCCTM
8. Symmetry: M.C. Escher & Scott Kim • Infinity SCCTM
8. Symmetry: M.C. Escher & Scott Kim • Tessellations SCCTM