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Contents, Interactive Mathematics Miscellany and Puzzles

Contents, Interactive Mathematics Miscellany and Puzzles
Since May 6, 1997You are visitor number E66B7E in base 20 Raymond Smullyan, a Mathematician, Philosopher and author of several outstanding books of logical puzzles, tells, in one of his books, a revealing story. A friend invited him for dinner. He told Smullyan that his teenage son was crazy about Smullyan's books and could not wait to meet him. Having told this story, would it be wise to announce up front what this site is about? |Contact||Front page||Index||Store|

Touch Mathematics The Order of Operations: PEMDAS Purplemath If you are asked to simplify something like "4 + 2×3", the question that naturally arises is "Which way do I do this? Because there are two options!" ...or I could multiply first: Which answer is the right one? It seems as though the answer depends on which way you look at the problem. To eliminate this confusion, we have some rules of precedence, established at least as far back as the 1500s, called the "order of operations". A common technique for remembering the order of operations is the abbreviation (or, more properly, the "acronym") "PEMDAS", which is turned into the mnemonic phrase "Please Excuse My Dear Aunt Sally". Parentheses (simplify inside 'em) Exponents Multiplication and Division (from left to right) Addition and Subtraction (from left to right) When you have a bunch of operations of the same rank, you just operate from left to right. Content Continues Below Simplify 4 + 32. I need to simplify the term with the exponent before trying to add in the 4:

Sudoku - Play, Share & Print Sudoku puzzles for free! u36824 Easy What is Sudoku? Sudoku is a number-placement puzzle. You start with an almost empty puzzle, which has some of the cells already filled with numbers. Your objective is to fill in the rest of the empty cells. According to the Sudoku rules, a number can appear only once in every row, column, or region (3X3). How do I start a Sudoku puzzle? The easiest way to begin is to choose a number and try to fill in all the places in the puzzle where it must appear, according to the Sudoku rules. Now what? Now go ahead! Maths Online - Free Maths Tuition For All Australian High School Students

Mathematical Images: Symmetry | MissQuinnMaths I love finding ‘maths pictures’, and thought it would be nice to start collecting and sharing them. Symmetry is the easiest to begin with, unsurprisingly. Images with simple line symmetry can be great for young (i.e. Y7) pupils to engage with, allowing for discussions about strategies to ‘test’ to how symmetrical an image is and how it could be improved to be ‘more’ symmetrical (this is a good ‘way in’ to using squared paper to complete reflections). Rotational symmetry is fun to explore with an interactive whiteboard, and more practical activities abound (e.g. for homework pupils can draw their own Rangoli patterns, or make patterned wedges that can be repeated to build up a whole shape). Some of my most able Y7 pupils wrote excellent pieces discussing symmetry in buildings and gave their opinions on how symmetry affected the attractiveness of a building or shop display. Some examples of line symmetry: Some examples of rotational symmetry: Post links to any images of your own! Like this:

Khan Academy From kindergarten to calculus, Khan Academy is here to help. Sharpen your skills with over 100,000 interactive exercises. Over 100,000 interactive exercises. You may have heard about our videos, but did you know that Khan Academy has fun interactive math exercises that cover skills ranging from counting to calculus, grade by grade? Created and peer-reviewed by a team of math educators, our exercises include full coverage of US Common Core and beyond, ranging from early math through calculus. Review student progress in real time. You will be empowered with instant, in-depth feedback and reports so you’ll know exactly where each student and your class as a whole stand at any time throughout the year. Stay up to date with your child’s progress. You’ll get quick email updates so you can see your children’s progress as they learn, both when they’ve mastered new skills and when they might be struggling.

Khan Academy Word Problems This page contains links to free math worksheets for Word Problems problems. Click one of the buttons below to view a worksheet and its answer key. You can also use the 'Worksheets' menu on the side of this page to find worksheets on other math topics. Addition Word Problems Introductory word problems for addition Subtraction Word Problems Introductory word problems for subtraction Mixed Addition and Subtraction Word Problems Mixed addition and subtraction word problems. Multiplication Word Problems Introductory word problems for multiplication. Division Word Problems Introductory word problems for division. Girl Scout Cookie Division If you've been working as Troop Cookie Mom (or Dad!) Division With Remainders Word Problems Story problems using division and involving remainders. Mixed Multiplication and Division Word Problems Mixed multiplication and division word problems. Mixed Operation Word Problems Mixed addition, subtraction, multiplication and division word problems. Printable Flash Cards

Balancing chemical equations worksheets Practice balancing 100's of chemical equations from simple to advanced. Each chemical equation worksheet comes with answers and can be downloaded as a pdf file. Chemistry worksheets for download Identification of salts from a variety of acid reactions What happens in a chemical reaction? Chemical reactions are like a ‘dance’. Old chemicals(reactants) rearrange to produce new chemicals(products) Reactants → Products The arrow means 'produces' In a chemical reaction atoms are rearranged as old chemical bonds are broken and new chemical bonds are formed.The 'law of conservation of mass' is supported as the weight doesn’t change between the mass of the reactants and the mass of the products. How to balance a chemical equation In balancing chemical equations you need to remember to three important points. You do not change the chemical formula of a substance to balance an equation. Example of how to balance a chemical equation Hydrogen + Oxygen →Water Check the number of atoms for each element.

Vi Hart: Math Doodling Remember that video about doodling dragons and fractals and stuff? I finally finished part 2! Here is a magnet link so you can dowload it via torrent. Here it is on YouTube: You can tell I worked on it for a long time over many interruptions (travelling and other stuff), because in order to keep myself from hating what was supposed to be a quick easy part 2, I had to amuse myself with snakes. Here was part 1, via Torrent or YouTube.