Napier's Bones
       for
Multiplication

Contents
Vocabulary bones / strips / stick multiples of a number References	Operations multiply divide take a square root	Manipulatives digital big paper smaller paper

Read Vocabulary First       You must know Napier's Bones vocabulary and multiples.       Read: Vocabulary

Multiply Multiply Any Numbers

1st: Think pencil & paper multiplication. The rows on the bones provide the rows of the multiplication problem. 2nd: Arrange bones for one number to the right of the index bone. 3rd: Identify a row for each digit of the multiplier.     Write the sum of the digits in each diagonal in the row, one digit per diagonal.   Carry as needed. This is the product of the 1-digit number by the multi-digit number. 4th: Lay out the problem as in a pencil and paper multiplication.     Let each row product serve as the corresponding row of the multiplication.     Remember to shift, indent, to the left to line up the correct place. 5th: The sum of the shifted rows is the final product.

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Instructions & Manipulatives Instructions on the Operations multiplication division root extraction   Manipulatives Napier's Bones Digital Manipulatives Napier's Bones big paper version Napier's Bones small paper version       Many other manipulatives on many different topics are found at: MathTokens.Com.

References Azzolino, Agnes "algorithm" © 2005 at www.mathnstuff.com/math/spoken/here/1words/a/a11.htm (last modified 2005), visited 10 April 2009. Azzolino, Agnes "Multiplication & Division" © 2008 at www.mathnstuff.com/math/algebra/tt15.htm#divide visited 10 April 2009. Azzolino, Agnes "multiple" © 2005 at www.mathnstuff.com/math/spoken/here/1words/m/m29.htm visited 10 April 2009. Wikipedia®', Wikimedia Foundation, Inc., "Napier's bones - From Wikipedia, the free encyclopedia" GNU Free Documentation License at http://en.wikipedia.org/wiki/Napier%27s_bones (last modified 16 March 2009, at 20:42 (UTC) ), visited 10 April 2009.

© 2009, October 2010, A. Azzolino www.mathnstuff.com/math/spoken/here/2class/60/nbonesm.htm