Sal Khan
A broad set of tutorials covering perimeter area and volume with and without algebra. Tired of perimeter and area and now want to measure 3-D space-take-upness. Well you've found the right tutorial. Enjoy! Source: Khan Academy (www.khanacademy.org), used under the Creative Commons Attribution-NonCommercial-ShareAlike (CC BY-NC-SA) license. All Khan Academy content is available for free at www.khanacademy.org. Khan Academy does not endorse the World Public Library.
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