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Pre-Algebra Skills (Math 20)

Math 20:








· Math

Math 20 Videos 

(recorded Spring 2018 at Clackamas Community College)

I hear a lot about Math Anxiety and for that I love to recommend this video:

My Mom Beth Josi is a motivational Speaker and she has been giving this seminar to help people my whole life: Winnervision (A video by Beth Josi to help motivate! Growth Mindset stuff):

I made these videos of my class lessons from a Math 20 class I taught.


Divisibility Rules:

Order of Operations:

Primes vs. Composite:

Prime Factorization:

Equivalent Fractions:

Equivalent Fractions and Adding Fractions:

Mixed Numbers & Improper Fractions:

Equivalent Fractions & Cross Products:

Multiplying Fractions:

Dividing Fractions:

Multiplying and Dividing Fractions:

Change mixed numbers to improper fractions before we multiply or divide:


Scientific Notation:


Solving Proportions:

Fractions, Decimals & Percent:

Percent Proportions:

Percent Word Problems:


Area, perimeter, and volume:

Pythagorean Theorem:

Integer Operations:

Subtracting Integers:

Multiplying & Dividing Integers:


Data, Mean, Median, Mode: