Curated OER
Proportions and Similar Figures
Duane demonstrates how to find a missing length in figures that are similar. In this example he uses two similar triangles.
Curated OER
Finding the Whole from a Percent
He draws, problem solves, and uses proportions to show how to determine how to find a whole from a percent. Good problem solving strategies are at work in this video on percent. This is a good video for learners with a basic...
Government of Alberta
Learn alberta.ca: Math Interactives: Rate/ratio/proportion (Video Interactive)
The use of rate, ratio, and proportion is illustrated in this video about action photography. An additional interactive element allows students to explore equivalent ratios equivalencies through enlarging and reducing images to compare...
PBS
Pbs Learning Media: Real Life Math: Woodworker
Listen to a master craftsman explain many of the ways that mathematics is used in woodworking, including number operations; geometry; ratios and proportions; and measurement. In the accompanying activity, students will draw a scale...
Math TV
Math tv.com: Basic Mathematics: Solving Proportions
A math teacher and several students offer step-by-step solutions to questions involving proportions. Questions include, "In the proportion 3/4 = 6/8, name the four terms, the means, and the extremes" and "Solve for x: 2/3 = 4/x". In the...
Math TV
Math tv.com: Basic Mathematics: Solving Proportions: Applications
A math teacher and his students provide step-by-step solutions to word problems dealing with proportions. Example questions include, "A recipe for 16 brownies calls for 2/3 cup of butter. How many brownies can be made from 1 cup of...
Sophia Learning
Sophia: Representing Fractions: Lesson 7
The purpose of this lesson is to demonstrate how to represent a fraction. It is 7 of 15 in the series titled "Representing Fractions."
Sophia Learning
Sophia: Scale: Lesson 8
In this lesson, you will learn about the Scale principle. It is 8 of 9 in the series titled "Scale."
Sophia Learning
Sophia: Equivalent Fractions: Lesson 9
In this lesson, the student will learn how to create two equivalent fractions by multiplying a fraction by a value of one. It is 9 of 12 in the series titled "Equivalent Fractions."
Planet Nutshell
Planet Nutshell: Math Shorts: Unit Rates
Planet Nutshell Math Shorts provide animated videos that explain various math topics. On this site students learn about unit rates.
Virtual Nerd
Virtual Nerd: How Do You Figure Out a Percent of Change?
In this tutorial, use real world problems to learn how to calculate the percent of increase using the percent of change formula. [3:36]
Virtual Nerd
Virtual Nerd:figure Out Whether a Percent of Change Is an Increase or a Decrease
In this tutorial, how the percent of change is found from the information given in a word problem is demonstrated. [7:00]
Khan Academy
Khan Academy: Ratios and Proportions: Understanding Proportions
This video shows how to determine if a given proportion is true or false.
Sophia Learning
Sophia: Equivalent Ratios
Students learn about equivalent ratios in this video lesson. The tutorial consists of detailed examples that explore the mathematics concept.
Sophia Learning
Sophia: Ratios and Proportions
Ratios and proportions are investigated in this mathematics resource. Two video lessons are provided to help students learn about the topics.
Sophia Learning
Sophia: Similar Polygons and Their Perimeters
Explore the relationship between similar polygons and the ratio of their perimeters. Assess learning with a quiz.
Sophia Learning
Sophia: Surface Area and Volume in Similar Solids
Determine if solids are proportional by calculating the surface are and volume. Assess learning wih a quiz.
Sophia Learning
Sophia: Using Similar Triangles to Make Indirect Measurements
This video lesson demonstrates how similar triangles can be used to make indirect measurements. Students can check their understanding with an assessment.
Sophia Learning
Sophia: Triangle Proportionality Theorem: Lesson 3
This lesson presents how to apply the triangle proportionality theorem to solve for unknown variables and side lengths. It is 3 of 6 in the series titled "Triangle Proportionality Theorem."
Virtual Nerd
Virtual Nerd:how Do You Solve a Problem Using Indirect Measurement With Shadows?
This tutorial explains how to take a word problem and use indirect measurement to turn it into a proportion, then use the mean-extremes property of proportions to cross multiply and solve for the answer. [4:22]
Imagine Learning Classroom
Learn Zillion: Convert Between Currencies and Find Exchange Rate
In this lesson, you will learn how to convert between two different currencies and find the exchange rate by solving proportions. [3:47]
Imagine Learning Classroom
Learn Zillion: Identify the Constant of Proportionality From a Diagram
In this lesson, you will learn how to identify the constant of proportionality from a labeled diagram by writing an equation of the form y=mx and solving for m. [3:56]
Next Vista for Learning
Next Vista for Learning: Finding the Whole From a Percent
Concept demonstration video [3:52] explains how to find the whole from a part and percent using three methods.
Khan Academy
Khan Academy: Dorothea Rockburne: Drawing Which Makes Itself
In this video [3:56] contemporary artist Dorothea Rockburne talks about mathematics, magic, and materials for artists. To learn about how art changes over time, enroll in one of MoMA's courses online. Created by The Museum of Modern Art.