Mathematics As A Second Language

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

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Preface Module 1:  The Development of Place Value Module 2:  Addition and Subtraction of Whole Numbers Module 3: Multiplication and Division of Whole Numbers 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 4:  Rational Numbers, Part 1 - Common Fractions Module 5:  Rational Numbers, Part 2 - Common Fractions Continued Module 6:  Rational Numbers, Part 3 - Percents and Mixed Numbers Module 7:  Rational Numbers, Part 4 - Introduction to Decimal Fractions Module 8:  Rational Numbers, Part 5 -  Quotient of Decimal Fractions   Supplement: The Calculator Module 9:  Introduction to Constant Rates Module 10: Applying Constant Rates to Measurement Module 11: Selected Topics in Non-Constant Rates                   Appendix 1: More on Rectilinear Figures  Module 12: Arithmetic As the Gateway to Algebra                   Appendix: A Note on Temperature Scales