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This section will cover the fundamentals of proportion application.
Setting up a proportion will reveal the missing part of an unknown ratio.
The key is matching up the quantities for both ratios correctly. Make sure that the quantities are the same on both sides.
For example: Let's say that we're showing the length and height of two items. We would set up our quantities as shown above.
Below are examples of how and when to use proportions to solve problems.
Example:
Sara drives 60 miles in 1 hour. How many miles will she drive in 5 hours?
Here's what we know: 60 miles = 1 hour
Since we're looking for the miles that Sara will drive in 5 hours, we will label our missing quantity as m for miles.
60 x 5 = 300
1 x 300 = 300
How to Set up a Proportion
Application of Proportions
Sara will drive 300 miles in 5 hours.
To see if your answer is correct, plug your answer back into the missing part of the proportion. Cross multiply.
Both sides are equal. The answer is correct!
Example:
Hint: Solve for m by moving m to the left of the equal sign.
A proportion is a statement that shows an equal relationship between two ratios (fractions).
Math: Application of Proportion - Tutorial
