Proportions
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In math, the word "proportions" means 2 ratios put into an equation. Some examples of proportions are:
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- 50⁄100 = 1⁄2
- 75⁄100 = 3⁄4
- x⁄100 = 3⁄4, where x = 75.
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, the proportion would be:
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- x⁄3.85 = $40⁄3.50
The solution is simply:
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- x = $40/3.50 x 3.85 = $44.00, or $4 more when $0.35 higher.
Many other common calculations can be solved by using proportions to show the relationships between the numbers.
