CK-12 Foundation
Using Ratios: Lesson
How do ratios work in geometry? The video answers just this question in order to help your class master an important skill. Using the concept of ratios, this segment in an extensive geometry playlist applies ratio reasoning to...
Math Antics
Proportions
Equivalent ratios lead to proportions. The video provides the definition of a proportion and provides examples of proportions. Using real-world examples, the resource shows how to solve for unknown quantities in proportions using the...
Math Antics
Ratios and Rates
Use ratios to compare numbers. The resource provides an explanation of the difference between fractions and ratios by pointing out that ratios are used to compare two quantities. The video introduces rates as special ratios that involve...
Fuse School 
Calculating Gas Volumes
How do scientists measure how much pollution a car gives off? Scholars build on their knowledge of the molecular volume of a gas in order to calculate gas volumes in chemical reactions. The 22nd video in a 30-part series uses...
Krista King Math
Ratio and Proportion for Chemical Compounds
Explore the strong connection between mathematics and science. Learners see how to use proportions to determine the makeup of chemical compounds. The example shown finds the number of grams of oxygen in a given amount of water.
Krista King Math
Ratio and Proportion, Word problems
Combine several mathematics concepts as classes solve linear systems. After writing a system of equations involving a proportion, learners then solve the system. A video instructor uses the substitution method and must work...
Krista King Math
Unit Multipliers
How many yards are in 360 inches? Pupils answer this question with the help of a video lesson. The instructor uses dimensional analysis to complete the conversion. 
Krista King Math
Ratio and Proportion
Teach your classes how to solve a simple proportion. A video tutorial explains the process of cross multiplying to solve a basic proportion. The instructor reinforces the meaning of a proportion by solving an example by inspection.
Krista King Math
Surface Area to Volume Ratio of Prisms
Increase pupil understanding of formulas as they apply surface area and volume calculations to determine ratios of different prism sizes. The examples include both a cube and rectangular prism. 
Brightstorm
Definition of Slope - Concept
Math can be a slippery slope. A video introduces the concept of slope, provides its definition, and shows examples of positive and negative slopes. It connect the examples to skateboard ramps to help pupils...
Brightstorm
Finding the Slope of a Line from a Graph - Concept
Explain how to find the slope of a graph of a line with a video that points out how no matter what two points are used on a graph of a line, the slope is the same. A few examples reiterate how to find the slope of vertical...
National Education Association
Rates and Proportions
Clarify complex math concepts with a helpful video. Learners view ways to work with ratios and proportions while discussing vocabulary and notation. After solving proportions, they apply the new strategy to word problems.
MinutePhysics
Where Was The Big Bang?
If you think the world revolves around you, think again! In this super-short clip, the narrator explains, accompanied by drawings, how scaling varies based on your frame of reference or vantage point. You might want to add this clip to...
Scholastic
Study Jams! Proportions
Join Zoe and Sam as they use proportions to budget money for their Green Earth Club. Watch as they set up and solve a series of proportions using cross multiplication and division. A great resource that brings together prior knowledge of...
Curated OER
How Do You Find the Sine of an Angle in a Right Triangle?
A trigonometric ratio is a ratio between two sides of a right triangle. In this problem, find sin(A) in the given right triangle. Use the ratio of the opposite side over the hypotenuse.
Curated OER
How Do You Find a Scale Factor in Similar Figures?
Three angles of one triangle are equal to the corresponding angles in another triangle. Use a ratio of corresponding sides to find the scale factor. Actually, there are two scale factor values. The instructor will explain how to get both...
Curated OER
How Do You Solve a Scale Model Problem Using a Scale Factor?
Scale drawings are used to represent many things. Scales are used all the time on maps, and in architectural drawings. Watch this video as the instructor illustrates a simple drawing of a blueprint to represent the footage of an actual...
Curated OER
How Do You Find the Scale of a Model?
A model car, a life size car, now compare their sizes. Hmmm. Ok, set up a proportion and then figure out a ratio, and now you can express the relationship in terms of scale. Watch this video and the teacher will demonstrate just how to...
Curated OER
How Do You Know If Two Ratios are Proportional by Reducing?
Working on proportional ratios in your class? This video might be for you! An instructor takes a step-by-step approach to reducing and comparing two ratios in order to determine if they are proportional. A clear video, this resource...
Curated OER
What's a Ratio?
Fractions are ratios. What? Yes! A ratio is a comparison of numbers, and a fraction is a way to write a ratio. There are a couple of other ways to write a ratio. Do any come to mind? Can ratios be found in the real world? Yes!...
Curated OER
What are Equivalent Ratios?
Work through a word problem with the help of a video tutor. You'll learn how equivalent ratios are just like equivalent fractions. Write a ratio as a fraction, reduce each ratio, then determine if they are the same. It's as simple as that!
Curated OER
How Do You Use Dimensional Analysis to Convert Units on Both Parts of a Rate?
The video just before this lesson showed how to do unit analysis and rate conversions. This lesson also shows conversion of unit rates, feet, miles, seconds, hours. So pay attention and learn how to figure out how many feet per second...
Curated OER
How Do You Set Up a Proportion from a Word Problem?
In this word problem, the skill to remember is to match up the similar measurements. This means the inches match up with the inches and the feet match up with the feet measurements. This problem is a ratio and is written as fractions....
Curated OER
How Do You Determine if Two Ratios are Proportional Using Cross Products?
Are these two given ratios proportional? One quick and easy way to answer this question is to cross multiply the two values. If the products are equal then they are proportional ratios. If they are not equal then they are not...
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
