 # Mathematics Lessons - 10 (Arithmetic Review For College)

This is a series of mathematics lessons that will review the important topics in arithmetics with examples and solutions.

In these lessons, you will learn Approximation, Addition, Subtraction, and Multiplication of Decimals.

These lessons will also be useful as a pre-Algebra review.
The videos are presented by the Portland Community College.

### Math 20 - Lesson 35

Approximation of Decimals

### Math 20 - Lesson 37

Subtraction of Decimals

### Math 20 - Lesson 38

Multiplication of Decimals
1) Multiply as if they were whole numbers (that is, disregard the decimal point)
2) Count the total number of decimal places in the factor (the multipliers)
3) Starting at the right end digit of the "answer", count off the same number of places
4) If more places are needed, insert additional zeros at the front.

Errata: (205.6)(0.312) = 64.1472

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