 page 2, How to Add, Subtract, Multiply, Divide Signed Numbers  Manipulatives
Signed Number Manipulative Page Menu  
Begin your work here with REPRESENTATION. It is the most important part of the page. Though four operations are listed here, there are really only three sets of instructions. This page justifies the algorithms for signed number computation listed on the last page. It also provides practice briefly and links to more practice on other pages.

Representing Signed Numbers Manipulatively  

Use bottle tops as token for numbers. Use headsup tops for positives. Use bottomsup tops for negatives.

How to Add Signed Numbers  

How to Subtract Signed Numbers  
Two methods for the manipulative operation subtraction are presented. The author prefers the first method because it parallels the terminology used in algebra classes. Some students prefer the second definition of subtraction because it is the definition they learned in first grade. A teacher should investigate both methods. A student should with practice be able to complete this subtraction menatlly, without the use of manipulatives. Two sets of RESTATE buttons permit examples of both computation methods. SUBTRACTION means ADD THE OPPOSITE.
SUBTRACTION means TAKE AWAY.

How to Multiply or Divide Signed Numbers  
Manipulatives are not the best format for the presentation of signed number multiplication or division. The "rules say:"
And an explanation based on factors and opposites is shown on the last page and on the Opposites on Your Computer's Calculator page. The explanation here involves money (the manipulative or token) and a win/loss (signed) monetray meaning for.

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