Texas Instruments
Texas Instruments: What's My Ratio?
In this activity, students use linear measurement and calculators to investigate proportionality and determine the constant ratio between similar figures.
PBS
Pbs Learning Media: Cyberchase: Bianca Gets in Gear
Bianca visits a bike shop and learns how bicycle gears work in this Cyberchase video segment. [3:26]
Science and Mathematics Initiative for Learning Enhancement (SMILE)
Smile: Similarity
This site contains a lesson plan for high school age learners. The objective is to discover the factor of proportionality in similar polygons and to relate this factor to the perimeters and areas of similar polygons.
Science Education Resource Center at Carleton College
Serc: Take a Deep Breath on the Appalachian Trail
A lesson plan that includes a PowerPoint learning module for students. They will examine spreadsheet data on air quality in Great Smoky National Parks, and solve problems using ratio and proportion. The exercises will help them to...
The Math League
The Math League: Ratio and Proportion
This tutorial provides definitions and examples of ratios and proportions and features comparing ratios and converting rates.
Oswego City School District
Regents Exam Prep Center: Ratios and Music
The class notes examine the connections between music and ratios. An example and additional questions on the concept are included.
Other
Cpa class.com: Ratios for Financial Statement Analysis
This site summarizes the most common financial statement analysis ratios and shows the formulas for calculating them. Click on "Annual Report Project" for additional related links.
Other
Sierra College: Summary of Tests for Series
Provides a summary of tests for series that includes the test, series, converges, sum of remainder, and diverges for nth Term, Geometric Series, Telescoping Series, p-Series, Alternating Series, Integral, Root, Ratio, Direct Comparison,...
Texas Instruments
Texas Instruments: Picturing Probabilities of Number Cube Sums
Students use ideas of ratio and proportion to investigate various ways to make a circle graph. Students create graphs to display the probabilities of the different sums that can be generated with two number cubes. [Requires Adobe Reader.]
Illustrative Mathematics
Illustrative Mathematics: 7.rp.3 Lincoln's Math Problem
The purpose of this task is for students to solve a multi-step problem involving simple interest. The Aligns with 7.RP.A.3. The task provides both a problem and the solution.
Mangahigh
Mangahigh: Number: Ratio and Proportion Drawings and Models
Explore ratios in terms of scales on a map.
CK-12 Foundation
Ck 12: Measurement: Unit Scale to Find Actual Dimensions
[Free Registration/Login may be required to access all resource tools.] Identify unit scale and use unit scale when problem solving.
CK-12 Foundation
Ck 12: Probability: Measurement of Probability Grade 6
[Free Registration/Login may be required to access all resource tools.] Express probability in the form of a fraction, decimal, or percent.
CK-12 Foundation
Ck 12: Statistics: Levels of Measurement
[Free Registration/Login may be required to access all resource tools.] This Concept introduces students to the different levels of measurement.
Other
School House Technologies: Free Math Worksheets for Teachers
A collection of math worksheets covering a multitude of math topics.
CK-12 Foundation
Ck 12: Arithmetic: Decimals as Percents
[Free Registration/Login may be required to access all resource tools.] Write percents as decimals and decimals as percents
CK-12 Foundation
Ck 12: Arithmetic: Equivalent Ratios
[Free Registration/Login may be required to access all resource tools.] Among rational numbers, identify and write different forms of equivalent ratios.
CK-12 Foundation
Ck 12: Arithmetic: Fractions as Percents Grade 6
[Free Registration/Login may be required to access all resource tools.] Convert given fractions into percentages.
CK-12 Foundation
Ck 12: Arithmetic: Fractions as Percents Grade 7
[Free Registration/Login may be required to access all resource tools.] Write fractions as percents by using proportions and equal ratios.
CK-12 Foundation
Ck 12: Arithmetic: Percents as Fractions
[Free Registration/Login may be required to access all resource tools.] Write percents as fractions in simplest form
CK-12 Foundation
Ck 12: Arithmetic: Ratios in Simplest Form
[Free Registration/Login may be required to access all resource tools.] In this lesson students simplify ratios by dividing by the greatest common factor. Students examine guided notes, review guided practice, watch instructional videos...
CK-12 Foundation
Ck 12: Arithmetic: Ratios in Simplest Form
[Free Registration/Login may be required to access all resource tools.] In this lesson students write ratios in simplest form. Students examine guided notes, review guided practice, watch instructional videos and attempt practice problems.
CK-12 Foundation
Ck 12: Chemistry: Mass Ratio Calculation
[Free Registration/Login may be required to access all resource tools.] Explains mass ratio definition and mass ratio calculations.