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Ratios and proportions

9 videos
2 skills
Would you rather go to a college with a high teacher-to-student ratio or a low one? What about the ratio of girls-to-boys? What is the ratio of eggs to butter in your favorite dessert? Ratios show up EVERYWHERE in life. This tutorial introduces you to what they (and proportions) are and how to make good use of them!

Introduction to ratios

VIDEO 14:13 minutes
What a ratio is. Simple ratio problems.

Ratios as fractions in simplest form

VIDEO 1:19 minutes
Ratios as Fractions in Simplest Form

Simplifying rates and ratios

VIDEO 2:28 minutes
Simplifying Rates and Ratios

Ratio word problem: boys to girls

VIDEO 2:04 minutes
In this example, we are given a ratio and then asked to apply that ratio to solve a problem. No problem!

Ratio word problem: centimeters to kilometers

VIDEO 1:12 minutes
Let's solve this word problem using what we know about ratios so far.

Ratio word problems

PRACTICE PROBLEMS

Proportion validity example

VIDEO 1:25 minutes
Understanding Proportions

Solving ratio problems with tables example 1

VIDEO 5:05 minutes
We're displaying ratios in a table format here, and then asking: given a ratio, solve for equivalent ratios. Here are a few examples to practice on.

Solving ratio problems with tables example 2

VIDEO 2:29 minutes
Let's compare 2 tables of ratios and interpret them to solve the word problem. This is a fun!

Solving ratio problems with graph

VIDEO 1:34 minutes
In this example we'll plot points on the x and y axis to reflect the given ratios.