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1  +2 2014 sep 06as there was impossibleThere are really impossible thingsThere are really impossible things: few examples with links to more detailed pages.
1  ~ 2014 aug 30what is a numberWhat's a number ? - Interactive Mathematics Miscellany and PuzzlesA number r is rational if it can be written as a fraction r = p/q where both p and q are integers. In reality every number can be written in many different ways. To be  ...
1  +2 2014 aug 29boolean logic gameBinary puzzle - Interactive Mathematics Miscellany and PuzzlesIn the Boolean Algebra , one normally defines conjunction (&, AND), ... The purpose of the game is to get all 16 squares filled with the right numbers which are ...
1  ~ 2014 aug 28tricks on quick mathmaicsFast Arithmetic Tips - Interactive Mathematics Miscellany and PuzzlesFast Arithmetic Tips, how to speed up calculations. ... E. H. Julius, More Rapid Math Tricks And Tips, John Wiley & Sons, 1992; S. Flansburg, Math Magic, William ...
1  ~ 2014 aug 21magic math tricksStunning Friends With Math MagicA collection of card tricks , number guessing games, paper and glue magic , and other math exercises. ‎A Baffling Prediction - ‎A Matter of Age - ‎An Arithmetic Magic Trick - ‎Magic in a Square
1  ~ 2014 aug 13math magic tricks
1  ~ 2014 aug 04what is trigonometryWhat Is Trigonometry ?Trigonometry defines relations between elements of a triangle. In a triangle, there are six basic elements: 3 sides and 3 angles. Not any three line segments may ...
1  ~ 2014 aug 01how to calculate fasterFast Arithmetic Tips: Getting the Result FastFast Arithmetic Tips, how to speed up calculations . It's often more convenient instead of multiplying by 5 to multiply first by 10 and then divide by 2, etc...
2  ~ 2014 sep 23euqivalence relationship symbolEquivalence RelationshipThe last one enables me to point out how omnipresent equivalence relations actually are. People invent symbols (known as words) to denote some objects.
2  ~ 2014 sep 21what is numberA number r is rational if it can be written as a fraction r = p/q where both p and q are integers. In reality every number can be written in many different ways. To be  ... ‎rational and irrational - ‎real and complex - ‎imaginary - ‎algebraic and transcendental
2  -1 2014 aug 26interactive math activitiesInteractive Mathematics ActivitiesInteractive Mathematics Activities for Arithmetic, Geometry, Algebra, Probability, Logic, Mathmagic, Optical Illusions, Combinatorial games and Puzzles.
2  ~ 2014 aug 20add list of numbersAdding a Long List of NumbersFor some people, adding a list of not very different numbers is a frequent task. To me this happens every time I feel my tax returns; there is always a few dozen ...
2  ~ 2014 aug 07the knot logoMy Logo - Interactive Mathematics Miscellany and PuzzlesA story of the Gordian Knot and Alexander the Great as related to my logo .
2  ~ 2014 aug 04probability and geometryGeometric ProbabilityGeometric Probability : definition and simple examples.
3  -1 2014 sep 27math glossaryMath Glossary , Math Terms, AGlossary of terms that have been discussed or mentioned on these pages. Letter A.
3  +3 2014 sep 20relationships matrixMatrices Help RelationshipsMatrices Help Relationships . Once when I was a graduate student I had a conversation with a philosophy professor friend about epistomology. He said there is a ...
3  ~ 2014 sep 18four 4Representation of numbers with four 4'sRepresentation of numbers with four 4's : 4/4*4/4 = 1, 4/4 + 4/4 = 2.
3  ~ 2014 sep 07pythagoras theoremPythagorean Theorem and its many proofsA collection of 43 proofs - some interactive - of the Pythagorean theorem .
3  ~ 2014 aug 29what is a pointWhat Is Point ? - Interactive Mathematics Miscellany and PuzzlesPoint is a basic concept of elementary geometry. The idea of point is an abstraction that distils our understanding of the concept of location.
3  +1 2014 aug 27mental math tricksFast Arithmetic Tips. Mental Calculations - Getting the result fast. Addition of 5. When adding 5 to a digit greater than 5, it is easier to first subtract 5 and then add  ...
3  ~ 2014 aug 25squaring the circleSquaring the Circle - Interactive Mathematics Miscellany and PuzzlesSquaring the Circle : it is impossible to construct a square equal in area to a given circle with compass and straightedge.
3  ~ 2014 aug 22sieve of eratosthenesSieve of Eratosthenes - Interactive Mathematics Miscellany and Sieve of Eratosthenes : an ancient way of getting the prime numbers. Eratosthenes (276-194 B.C.) was the third librarian of the famous library in Alexandria and ...
3  ~ 2014 aug 22rule of productThe Basic Rules of CountingBasic Rules : sum and product rules . Definitions and examples.
3  ~ 2014 aug 20interactive puzzle gamesMath Games - Interactive Mathematics Miscellany and PuzzlesMath games and puzzles , most illustrated with Java applets. Short Illustrated list.
3  -1 2014 aug 08maths circle diagram puzzlesEight Digits Puzzle - Interactive Mathematics Miscellany and PuzzlesPlace eight digits 1 through 8 into eight circles , but there is a caveat. ... The diagram can of course be looked at as a graph whereas the digits are being assigned ...
3  ~ 2014 aug 05water jug problemThe Three Jugs Problem . Introduction and a storyowed his interest in mathematics to a chance encounter with a simple problem : Two friends who have an eight-quart jug of water wish to share it evenly.
3  ~ 2014 jul 30a straight lineEquations of a Straight LineEquations of a Straight Line : a line through two points, through a point with a given slope, a line with two given intercepts, etc.
3  ~ 2014 jul 24cartesian coordinate systemCartesian Coordinate System - Interactive Mathematics Miscellany Cartesian Coordinate System : an interactive tool, definitions and examples.
3  -2 2014 jul 21mathematical induction examplesMathematical Induction - Interactive Mathematics Miscellany and Mathematical Induction . Definitions and examples of induction in real mathematical world.
4  +1 2014 oct 04towers of hanoiTower of Hanoi - Interactive Mathematics Miscellany and PuzzlesThe Tower of Hanoi puzzle was invented by the French mathematician Edouard Lucas in 1883. We are given a tower of eight disks (initially four in the applet ...
4  ~ 2014 sep 28binary systemHistory of the Binary SystemBinary System : history of invention, what it is, Euler's derivation.
4  -1 2014 sep 25random walk puzzleRandom Walks - Interactive Mathematics Miscellany and PuzzlesRandom Walks . A random walk is a formalization of a discrete process wherein a random selection is made between two alternatives (often ~+mn~1) at fixed ...
4  -1 2014 sep 21math magicA collection of card tricks, number guessing games, paper and glue magic , and other math exercises.
4  ~ 2014 sep 17do you know thatDid you know that ... Random interesting math facts, part 1. ... Everything you can do with a ruler and a compass you can do with the compass alone; Among all shapes with the same perimeter ...
4  ~ 2014 sep 16behind door number 1Monty Hall Dilemma - Interactive Mathematics Miscellany and PuzzlesSuppose you're on a game show, and you're given the choice of three doors . Behind one door is a car, behind the others, goats. You pick a door , say number 1 , ...
4  ~ 2014 sep 1052 royal pokerExample: A Poker HandPoker uses the standard deck of 52 cards. ... The highest ranking poker hand is a Royal Flush - a sequence of cards of the same suit starting with 10, e.g., ...
4  -1 2014 sep 07parabolic reflectorParabolic Mirror , TheoryParabolic Mirror : the tangent to parabola at a point bisects the angle between the segments joining the point to the focus and the directrix.
4  -1 2014 sep 07equivalence relationsEquivalence relations - Interactive Mathematics Miscellany and Equivalence Relationship. Examples, definition. Equivalence relations permeate mathematics with several salient examples readily available.
4  ~ 2014 sep 06base conversionImplementation of Base Conversion Algorithms from Interactive Base conversion algorithm: interactive implementation in different bases,binary- octal-hexadecimal conversion.
4  ~ 2014 aug 19what is geometryWhat Is Geometry ? - Interactive Mathematics Miscellany and PuzzlesGeometry is perhaps the most elementary of the sciences that enable man, by purely intellectual processes, to make predictions (based on observation) about ...
4  -1 2014 aug 12what is infinityWhat Is Infinity ? - Interactive Mathematics Miscellany and Puzzlesquestions a curious student may ask a math teacher is whether 1/0 is infinity or not. And then of course comes another thoughtful extension: Is 1/ infinity = 0?
4  -1 2014 aug 09did you know thatDid you know that ..., part 1. Random mathematical facts, There are one-sided surfaces.
4  -3 2014 aug 08facts about mathematicsDid you know that... Random interesting math facts, part 1. Random mathematical facts , There are one-sided surfaces.
4  +2 2014 jul 27nine dots puzzle9 Dots Problem - Interactive Mathematics Miscellany and PuzzlesThe 9 Dots Problem: try to lift some implicitly imposed constraints. ... One classical example is where nine dots are arranged on the sides and the center of a ...
4  +2 2014 jul 19equal to signLess than, Equal to, Greater Than Symbols from Interactive The symbol of equality is used to make a statement that the two differently looking expressions are in fact equal . For example, 1 + 1 does not look like 2 but the ...
5  -2 2014 sep 29pmwiki delete pageDeleting Pages - Interactive Mathematics Miscellany and PuzzlesTo delete a page , edit the page , select (highlight) all text in the edit textarea and ... This page may have a more recent version on pmwiki .org: ...
5  ~ 2014 sep 27less than symbolLess than , Equal to, Greater Than Symbols from Interactive The symbol of equality is used to make a statement that the two differently looking expressions are in fact equal. For example, 1 + 1 does not look like 2 but the ...
5  -2 2014 sep 20math puzzlesInteractive Mathematics Miscellany and PuzzlesAn encyclopedic collection of math resources for all grades. Arithmetic games, problems, puzzles , and articles.
5  +17 2014 sep 15modulo 7Modular arithmetic, examples, applications2222 5555 + 5555 2222 = 3 5555 + 4 2222 ( mod 7 ). There are only 7 residue classes modulo 7 . Therefore, the series of powers of a given number ( modulo 7 ) is ...
5  -1 2014 sep 14mathematical puzzles
5  -1 2014 sep 14tower of hanoi
5  -1 2014 sep 14hausdorff distanceHausdorff Distance - Interactive Mathematics Miscellany and PuzzlesHausdorff Distance . We talk about points in a space, like in the definition of a circle as a set of all points equidistant from a given point. But we have already ...
5  ~ 2014 sep 13معمای send more money100 Prisoners and a Light BulbEach of n prisoners will be sent alone into a certain room, infinitely often, but in ... one prisoner will turn on the light, and no prisoner turns it on more than once.
5  -2 2014 sep 09mathe matical puzzels
5  -2 2014 sep 06maze of mirrors wikiMirror Maze - Interactive Mathematics Miscellany and PuzzlesMirror Maze : navigate a maze of mirrors to cover all available cells in a square grid. ... Home · Wiki ; Subjects. What is What · Algebra · Arithmetic · Geometry ...
5  +2 2014 sep 02more things impossibleThere are really impossible things There are really impossible things : few examples with links to more detailed pages.
5  ~ 2014 aug 20silver dollar gamesThe Silver Dollar GameThe Silver Dollar Game - a modification of bogus Nim that may not on first glance look like a Nim variation.
5  +24 2014 aug 18tricks in mathsA collection of card tricks , number guessing games, paper and glue magic, and other math exercises.
5  +1 2014 aug 11math is artIs Mathematics Beautiful?Mathematics , as much as music or any other art , is one of the means by which we rise to a complete self-consciousness. The significance of Mathematics resides ...
5  +3 2014 jul 26lcm and gcdGCD (M, N) x LCM (M, N) = M x N - Interactive Mathematics GCD (M, N) × LCM (M, N) = M × N. A graphical illustration of the fact that the product of two integers equals the product of their gcd and lcm .
6  +5 2014 oct 01straight line
6  +3 2014 sep 29mathematical puzzle
6  +1 2014 sep 28poker royal 52
6  -4 2014 sep 27proofsProofs in MathematicsProofs , the essence of Mathematics - beautiful proofs , simple proofs , engaging facts. Proofs are to mathematics what spelling (or even calligraphy) is to poetry.
6  +95 2014 sep 26iknow that math, part 1. Random mathematical facts, There are one-sided surfaces.
6  +3 2014 sep 20maths tricks
6  -1 2014 sep 14forty legWhat do you call a centipede?This fellow has only 30 to 40 legs and a relatively short body. In a strange kind of a way it's classified as related more to the millipedes than to the centipedes.
6  -2 2014 aug 23languages of mathMathematics as a LanguageMathematics as a language . Expressing things differently. Blake wrote: I have heard many People say, 'Give me the Ideas. It is no matter what Words you put ...
6  +1 2014 aug 18what is an algorithmWhat Is Algorithm ? - Interactive Mathematics Miscellany and PuzzlesSimple as the definition of the notion of algorithm is, the concept of what it attempts to convey is a matter of debate and scientific research.
6  ~ 2014 aug 13what is algebraWhat Is Algebra ? - Interactive Mathematics Miscellany and PuzzlesBut when we come to the end of our arithmetic we do not content ourselves with guesses; we proceed to algebra -- that is to say, to dealing logically with the fact ...
6  ~ 2014 aug 12block n rollBlock ' N Roll - Interactive Mathematics Miscellany and PuzzlesBlock ' N Roll : a devilish puzzle. Roll a 2x1x1 block over available squares and seeze it into a whole. Do not fall over the edge!
6  +3 2014 aug 01magic numbers in mathematics
6  -2 2014 jul 29empty lable boxBox Labels - Interactive Mathematics Miscellany and PuzzlesIn the applet, select box . One of the two balls it contains will pop up. After which you'll have to drag labels (they will appear at the right moment) into the empty  ...
6  ~ 2014 jul 26pi in natureThe Nature of PiThe Nature of Pi : objects have shape and size. Objects of the same shape are similar. Existence of Pi follows from the fact that all circles have the same shape.
7  +14 2014 sep 26universal product codeUniversal Product CodeUniversal Product Code . Modulo arithmetic activity.
7  +3 2014 sep 24pmwiki authuser signupCTK Wiki Math - PmWiki - FAQPmWiki is a wiki-based system for collaborative creation and maintenance ...... Is there a way that people could self- register through AuthUser ?
7  +3 2014 sep 23block and rollBlock 'N Roll - Interactive Mathematics Miscellany and PuzzlesBlock 'N Roll : a devilish puzzle. Roll a 2x1x1 block over available squares and seeze it into a whole. Do not fall over the edge!
7  +1 2014 sep 20mathmagicFast Arithmetic Tips, Stunning Friends With Math Magic .
7  -2 2014 sep 19guess your number gameNumber Guessing Game . All by ComputerNumber Guessing Game , an example of usefulness of the binary system. Computer does ... In this simple game , your computer does all the work. You only have ...
7  -3 2014 sep 16other sitesOther sites - Interactive Mathematics Miscellany and PuzzlesRecommended math sites . A very exclusive collection of links of exceptionally worthy sites .
7  +1 2014 sep 12maths puzzles
7  -2 2014 sep 09how to do proofsProofs are to mathematics what spelling (or even calligraphy) is to poetry. Mathematical works do consist of proofs , just as poems do consist of characters.
7  +6 2014 sep 05coordinate axis lineCartesian Coordinate System : an interactive tool, definitions and examples. ... A straight line with an associated direction, a selected point and a unit length is ...
7  -1 2014 sep 05sam loyd puzzlesSam Loyd's Geometric PuzzleI've been thumbing through Mathematical Puzzles of Sam Loyd selected and edited by Martin Gardner (Dover, 1959), when I came across a puzzle whose set  ...
7  -6 2014 aug 28interactive math exercisesInteractive Mathematics Activities for Arithmetic, Geometry, Algebra, Probability, ... and the Least Common Multiple · Compare Fractions: Interactive Practice  ...
7  +11 2014 aug 27math short cutsStunning Friends With Math Magic · Divisibility Criteria ... A. Benjamin and M. Shermer, Secrets of Mental Math , Three Rivers Press, 2006. ... Movie shortcuts
7  -2 2014 aug 23alabama the knotThe Constitution and Paradoxes. In another demonstration of the Alabama paradox, for all sizes between 350 and 400, but 357, the state of Colorado would get three seats, with  ...
7  -1 2014 aug 20probability sample spaceSample Spaces and Random VariablesA random variable is a function defined on a sample space . We shall consider several examples shortly. Later on we shall introduce probability functions on the  ...
7  +2 2014 aug 17mind reading puzzleHummer's Mind ReaderThe computer is going to read your mind and announce which one you've been thinking .... Mind Reader from Interactive Mathematics Miscellany and Puzzles .
7  ~ 2014 aug 16bayes theorem examplesBayes ' Theorem - Interactive Mathematics Miscellany and PuzzlesBayes ' Theorem : definitions and non-trivial examples . ... Bayes ' Theorem . Bayes ' theorem (or Bayes' Law and sometimes Bayes' Rule) is a direct application of ...
7  +8 2014 aug 16mid reading puzzle
7  -2 2014 aug 12bulls and cowsBulls and Cows - Interactive Mathematics Miscellany and PuzzlesBulls and Cows : a mastermid variant where one has to guess the values of the hidden digits. But where are the bulls? And which ones are the cows? I do not ...
7  +1 2014 jul 29stack of coinsA Stack of Fake CoinsThere are 10 stacks of 10 identical-looking coins . All of the coins in one of these stacks are counterfeit, and all the coins in the other stacks are genuine.
7  -2 2014 jul 27greater than symbolLess than, Equal to, Greater Than Symbols . If A and B are two constant expressions, we write A = B if they are equal, and A ≠ B, if they are not. For example, for ...
8  -3 2014 sep 27maths puzzle
8  -1 2014 sep 26x y ²A Mathematical Rabbit out of an Algebraic HatThe proof depends on the following identity that holds for non-negative x, y, z: (2). x³ + y³ + z³ - 3xyz = ½(x + y + z)(( x - y ) ² + (y - z)² + (z - x)²). which is just another ...
8  +1 2014 sep 23abaccusAbacus and Its RelativesAbacus and Its Relatives: an introduction, a little history and clasification.
8  +2 2014 sep 20hypercycloid wikiHypocycloids - Interactive Mathematics Miscellany and Puzzles>Here I wish to consider a special case of hypocycloids where the radius r of the rolling circle k is exactly half that of the fixed circle K, ... Home · Wiki ; Subjects.
8  -3 2014 sep 13levenshtein distanceDistance between stringsProperties of distance. Distance between strings, Hamming distance, Levenshtein distance .
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