submitted by: Jeff LeMieux, August 2003This narrative describes how I use my javascript tool, cataloged in the Math Tools digital library, in the classroom.
Course: Math 7
Topic: Ratio and Proportion
Resource type: JavaScriptResource location:
http://www2.whidbey.net/ohmsmath/webwork/javascript/perprop.htmlMath Forum catalogue entry:
http://mathforum.org/mathtools/tool.html?rc=tool&new_id=1574Story: While there are a number of approaches for solving problems involving percentages, the percentage proportion equation is one of the easiest to remember. Simply stated, most simple proportions involving percentage can be 'inserted' into this equation. The solution is similar to solving a proportion and is presented as pencil and paper solutions, calculator solutions and this script. Normally this process would be introduced after a review of solving proportions.
Typical Questions
12% of what number is 6?
6 is what percent of 92?
What is 22% of 19?In the first question, the unknown is OF what number. The unknown goes in the OF spot, 12% goes in the % spot and 6 belongs to the IS space. That would give the proportion 6:x::12:100. The other problems would be similar in set up.
Where and how I used this: After the lesson introduction and practice this script is generally provided as a part of the lessons assignment page for the week on the web. It is presented as an alternative solution tool to both the pencil/paper and calculator methods of soltion.
As part of a practice/review session, there is another script available http://syzygy.virtualave.net/perpro.htm which provides problems (and answers). Typically, students will be assigned these as a speed drill to enhance problem set-up and labelling of answers.
The graphic on this page is the property of Jeff LeMieux and is available free for educational use. Most browsers allow you to right click on the image and save it to your machine.
Send comments to Jeff LeMieux at tackweed@whidbey.net
Jeff LeMieux August 2003
http://www2.whidbey.net/ohmsmath
