π is an irrational number, which means it CANNOT be written as a terminating decimal (like 3.14) or a fraction (like 22/7). Both 3.14 and 22/7 are only approximations. π is defined as the ration of the circumference of a circle to its radius. Click this link for a cool video someone else made showing why π is close to 22/7. Alternative Arithmetic Methods (I think these are easier ways to add, multiply, etc.) Moebius (Mobius) Strip: This is a real video where you actually see me as we use paper, scissors, and tape, and discover how to make a Moebius strip, as well as some very cool things about it: http://youtu.be/1xKiSSVY5bI Multiply by 5 the easy way even when you have decimals: http://www.youtube.com/watch?v=2wPAo5YAEfI Scratch Addition (scratchadd.mp4): Show a quick and easy way to add a column of single digit numbers using the Scratch or Dot Method. http://youtu.be/aobn006_rl0 Multiply by 9 the easy way This video shows you easy ways to multiply single digits by 9, and larger numbers when all the digits are the same, like 88888 x 9...really easy and fun to do!http://www.youtube.com/watch?v=VFHDn4TKHDM Numerals Shows the original numerals and the code for how it was obvious what each numeral stood for. These are referred to as the Arabic numerals, the Hindu numerals, Hindu-Arabic numerals and/or the Indian numerals. I do not know the exact origins. http://www.youtube.com/watch?v=bwQpCJroCac Squaring numbers whose digits are all ones; fun pattern for multiplying numbers by themselves (squaring) if all its digits are 1....like 11 x 11 or 11111 x 11111, etc. Show your friends! http://www.youtube.com/watch?v=xTffv1lpwGg Square Numbers that end in 5 such as 85 time 85, etc.: http://www.youtube.com/watch?v=Jeh83AoJ0v4 Videos by others: Calculus: This is the Derivate Rag (a song about how to remember how to take derivatives): http://www.youtube.com/watch?v=lQElwkuyiks |

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