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This page provides a list of educational videos related to Using Proportions. You can also use this page to find sample questions, apps, worksheets, lessons , infographics and presentations related to Using Proportions.
How to use Ratios and Proportions to Solve Real World Problems
By mrtedmartin
Instructor uses a Power Point presentation to demonstrate how to use ratios and proportions to solve problems real world problems. Unit rates are discussed and definitions are given. Solving unit rate problems are modeled and a calculator is used for computation.
Using Cross Multiplication to Solve Proportions
By Davitily
The instructor uses an electronic chalkboard to demonstrate how to use cross multiplication to solve for a missing variable in a proportion. One example is modeled using a step by step approach.
DEPRECATED Rational number word problems
By Khan Academy
Use your knowledge of proportions and fractions to determine shareholders profit in this word problem.
Mountain height word problem
By Khan Academy
Using some basic algebra to solve what looks like a hairy word problem that involves proportions.
Pythagorean theorem proof using similarity | Geometry | Khan Academy
By Khan Academy
Watch this video to see a proof of the Pythagorean Theorem that uses properties of similar triangles. Remember, similar triangles have congruent angles (equal angles) and proportional corresponding sides.
Speed translation | Ratios, proportions, units, and rates | Pre-Algebra | Khan Academy
By Khan Academy
This video takes us through some more advanced unit conversion problems. Here, we can see how to make multiple conversions in the same problem concerning speed. Take particular note of how the units change in each step. More importantly, note how, step by step, our units slowly change into the units we want for our final answer. If you are having trouble understanding why this happens, go to the key concept described at 2:20 in the video. Note that this only occurs when multiplying two quantities, not when adding them!
Finding average speed or rate | Ratios, proportions, units, and rates | Pre-Algebra | Khan Academy
By Khan Academy
Using the formula for finding distance we can determine Usian Bolt's average speed, or rate, when he broke the world record in 2009 in the 100m. Watch.
Example: The six trig ratios
By Khan Academy
Worked example where we walk through finding the major trig ratios
Trig Ratios - Part 2
By Papapodcasts
This is a video lecture course on Basics of Trigonometry and Geometry.
Trigonometry - The Trig Ratios, sin x, cos xand tan x : ExamSolutions
By ExamSolutions
In this tutorial you are shown how the sin, cos and tan ratios compare two sides of a right angled triangle.. You need to know this before calculating lengths and angles of right angled triangles. To see this video and other go to ExamSolutions at http://www.examsolutions.co.uk/
Solve Problems Involving Rates and Ratios
By Khan Academy
Watch this video as the instructor clearly explains how to solve a word problem involving finding unit rates. When rates are expressed as a quantity of 1, such as 2 feet per second or 5 miles per hour, they are called unit rates. See how you can apply this process to help you solve similar problems.
Trig Ratios - Part 1
By Papapodcasts
This is a video lecture course on Basics of Trigonometry and Geometry..
Trig Ratios of Special Angles Part 2
By AlRichards314
Youtube Presents Trig Ratios of Special Angles Part 2 an educational video resources on english language arts.