Name: Steve

Who is asking: Student
Level: Secondary

Question:
Where would you use a proportion and/or a ratio in a real life job or problem.

There are many examples for ratios and proportions in real life such as:

Your car gets 50 km/gallon and your gas tank holds 25 gallons. How far can you go on a tank of gas? You use proportions to solve this:



You can use ratios and proportions to compare the size and price of grocery store items to see which is the most economical (most stores have this "price per unit size" on the shelf tag already figured out).

There has been a recent study of the use of proportion in Nursing - calculating doses of drugs, and how to dilute them for different people (where the dosage is by weight, or by stage of the treatement).

One of the interesting things was HOW the practicing nurses computed proportions etc. Not the text book way at all! There is a note on this stude called Proportional Reasoning by Nurses on the Mathematical Association of America Web site.