Instructional Video9:34
Khan Academy

Similar Triangles, Similarity, Geometry

9th - 10th
Although a rather complicated topic, this video clearly explains the concept of solving problems involving similar triangles. It employs problem-solving to determine whether two figures are similar triangles. In addition, it provides...
Instructional Video9:55
Khan Academy

Similar Triangles (Part 2), Similarity, Geometry

9th - 10th
Building on concepts in the first part of the series on similar triangles, installment number two explores how to find the values for given angles in a triangle. These problems are solved by using algebra and ratios. A step-by-step...
Instructional Video3:58
Khan Academy

Introduction to Ratios, Ratios, Rates, and Percentages, 6th Grade

7th - 9th
Demonstrating the concept of ratios with several simple examples (animals, fruit, girls and boys in class), Sal guides viewers through finding and simplifying ratios. Even those who have difficulty grasping the concept of ratios will...
Instructional Video
Khan Academy

SAT Prep: Test 5 Section 3 Part 1

9th - 12th
Sal starts a new set of practice SAT problems in this video, starting on page 652 of The Official SAT Study Guide. Problems involve fractions and ratios, simplifying equations, and finding the perimeter of given coordinates on a plane.
Instructional Video
Khan Academy

SAT Prep: Test 4 Section 8 Part 2

9th - 12th
Young mathematicians will appreciate Sal's careful - yet efficient - methods for solving these typical SAT problems. He takes care to explain problems 8-12, but gets cut off in the middle of problem 12 (to be continues in the next video).
Instructional Video
Khan Academy

SAT Prep: Test 1 Section 9 Part 1

9th - 12th
With a brand new review session, Sal addresses common skills required to take - and pass - the SAT. He uses problems 1-4 on page 423 of The Official SAT Study Guide to demonstrate solving problems with linear equations, ratios, and...
Instructional Video9:25
Khan Academy

SAT Prep: Test 5 Section 9 Part 1

9th - 12th
Reasoning through the methodology of a new set of problems from page 679 of The Official SAT Study Guide, Sal shows students how to find the ins and outs of increasingly difficult math problems. He advises them to thoroughly think over...
Instructional Video
Khan Academy

SAT Prep: Test 2 Section 6 Part 1

9th - 12th
Using The Official SAT Study Guide, Sal begins another review session of eighteen problems, six of which are addressed in this video. The problems involve variables in linear equations, angles and parallel lines, and ratios. One problem...
Instructional Video8:30
Khan Academy

SAT Prep: Test 5 Section 7 Part 5

9th - 12th
Geometry problems on the SAT are often the most difficult for students to solve, let alone master. Focusing on several geometry-related skills (as well a few algebra problems), Sal makes this lesson a valuable resource for viewers who...
Instructional Video
Khan Academy

SAT Prep: Test 7 Section 5 Part 4

9th - 12th
Transitioning between algebra and geometry is no problem for Sal as he deftly solves these practice SAT problems. Mathematicians who have a hard time moving between skill sets will appreciate the way that Sal addresses each new problem...
Instructional Video4:12
Curated OER

How Do You Find a Scale Factor in Similar Figures?

6th - 10th
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...
Instructional Video4:54
Curated OER

What are Equivalent Ratios?

6th - 8th
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!
Instructional Video1:42
Curated OER

Map Scale and Ratios

3rd - 8th
Introduce you map scale and ratios lesson with this informative video. A student demonstrates how to properly use a scale on a map, as well as read a topographic map. This is a fantastic video to show during your map unit!
Instructional Video4:48
Curated OER

How Do You Find a Scale Factor in Similar Figures?

6th - 12th
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...
Instructional Video3:34
Math Playground

How Do You Solve a Ratio Word Problem?

5th - 7th Standards
Review how to calculate ratios using this film. The instructor works through word problems involving a ratio. This is a wonderful way to make ratios easier to understand.
Instructional Video2:47
Math Playground

What is a Ratio?

4th - 6th Standards
Explore the concept of ratios with this film. Using pennies and nickels, an instructor shows how to describe a ratio. However, I think the use of money might be a bit confusing. Prior to showing this video, you may want to clarify that...
Instructional Video1:30
Math Playground

What are equal ratios?

4th - 6th
Using a visual means, this video explores comparing ratios. This is a terrific way to approach the topic since it is a difficult concept for learners to understand. It is worth showing to the whole class, every mathematician can benefit...
Instructional Video2:18
Curated OER

Finding Equivalent Ratios

5th - 8th
Duane explains the process needed to determine if two fractions are equivalent. There are two ways to do this, in one scenario he compares two fractions and multiplies by two to determine that the two fractions are equivalent. In the...