Hello Deanna,

Worksheet 10-2 is giving the child more time to use the communitve law.

In another post to this same question Dr. Cotter replied,

"Worksheet 10-2 asks the child to find the sums by applying (underline added) the commutative law. For example, in 1 5, it is much easier to think of 5 1 than 1 5. That's using the commutative law.

Joan A. Cotter, Ph.D.
RightStart Mathematics by Activities for Learning, Inc.
http://www.alabacus.com "

Hope that helps with why that worksheet is there.

Thank you for giving your child a RightStart in Math,

Carissa
RightStart™ Mathematics by Activities for Learning, Inc.

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