In mathematics, the word "proportions" means two ratios put into an equation.[1] Some examples of proportions are:
In algebra, proportions can be used to solve many common problems about changing numbers. As an example, for the increase in a $40 purchase of gasoline (petrol), if the price rose 35 cents, from $3.50 to $3.85, then the proportion would be:
The solution is simply:
Many other common calculations can be solved by using proportions to show the relationships between the numbers.
In statistics, a proportion is a number which measures the extent to which a specific characteristic is in a sample or a population. It can be thought of as a percentage. To represent a sample proportion, the letters can be used. To represent a population proportion, the letter can be used.[2]