Arithmetic Videos
To ensure that the logic underlying place-value arithmetic is internalized, please do not use calculators until completing the first 8 videos.

To view videos, click on the links below. The exercise set solution videos illustrate complete solutions of the Form B exercise set in each module. 

Module1: Solutions Exercise Set 1 Form B

Module 2: Solutions Exercise Set 2 Form B

It is now common to define 3×4 to mean 3+3+3+3, i.e.; to add the number three together four times.  When multiplication is defined this way, the number on the right (4) is called the multiplier meaning the number of times the number 3 is added together. By the commutative property of addition, 3x4 is equal to 4x3.  In our video #3, Herb writes the problem 3+3+3+3 as 4x3 in order to illustrate the algorithm for multiplication in a more natural way. Notice that 4 (the multiplier) is in the first position.  Do not let this confuse you - they are equivalent definitions.

Module 5: Solutions Exercise Set 5 Form B

Module 6: Solutions Exercise Set 6 Form B

Module 7: Solutions Exercise Set 7 Form B

Module 8: Solutions Exercise Set 8 Form B

Module 9: Solutions Exercise Set 9 Form B

Module 10: Solutions Exercise Set 10 Form B

Module 11: Solutions Exercise Set 11 Form B

Module 12: Solutions Exercise Set 11 Form B

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We wish to acknowledge the support of the Gabriella and Paul Rosenbaum Foundation in helping us develop the content on this website.  Without the support of the Foundation and its president, Madge Goldman, much of the material that will be posted here would not have existed.

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