Mathematics and Multimedia Carnival 20

Welcome to the 20th edition of the Mathematics and Multimedia Blog Carnival - Dartboard Edition.  Here are the posts I have collected this month; some from the blog carnival site and some from my RSS Feed.

Before we begin a carnival, let's have some trivia about the number 20.

• The number of sectors in a dartboard.
• The atomic number of calcium. 
• It is the smallest primitive abundant number
• The number of faces of an icosahedron
• Can be written as the sum of the three Fibonacci numbers: 13 + 5 + 2

Now, let the carnival begin!

Math and Multimedia Carnival will be hosted here

The Mathematics and Multimedia Carnival is on its 20th edition and will be hosted here.  If you have a blog post about school mathematics, mathematics teaching and learning, multimedia tools, or any related article, you may submit here or email me directly at mathandmultimedia@gmail.com.  The deadline of submissions is on February 18, 2012 and the post date is on February 20.

You may want to visit the following recent math carnivals:

• last month's edition of the Math and Multimedia Carnival
• Math Teachers at Play 46 
• Carnival of Mathematics 85

To those who do not know what a carnival is, I have written a carnival primer in Math and Multimedia. 

GeoGebra 4.0 Tutorials and more...

This is to inform everyone that I am currently updating my GeoGebra Tutorials in Mathematics and Multimedia. I have updated the following tutorials so that they are compatible to GeoGebra 4.0.

• Introduction to GeoGebra
• GeoGebra Essentials 1 – Locating the Triangle’s Centroid
• GeoGebra Essentials 2 – Constructing a Rectangle

I will be updating three or more tutorials this weekend. If you are new to GeoGebra, I have created more than 50 GeoGebra tutorials categorized as follows.

• GeoGebra Essentials Series (10 tutorials for beginners)
• GeoGebra Basic Geometric Construction Series (7 tutorials for beginners)
• GeoGebra Intermediate Series (30 tutorials for beginners and intermediate users)
• GeoGebra Advanced (10 tutorials for advanced users)
• GeoGebra 4.0 Sneak Peek (New!) – 10 posts about GeoGebra 4.0

Please share the tutorials to people who might be interested.