This is an Honor's Math PowerPoint presentation that I assisted my son with.

1. Proportions for Pros
Honors Math/3rd Period
Ms. Shelly Brown-Jones 7-5
Presented by Justice Adams

2. Objective
• To define a proportion and its parts and terms.
• To exemplify the method of determining what
constitutes a proportion and what does not (and
to establish proportion to find missing terms).
• To demonstrate examples of proportions and
non-proportions.

3. Defining a Proportion

4. Showing Ratios
• 1 boy for every 3 girls = 1:3
• ¼ boys ¾ girls (a whole equals 4/4)
• 25% or 0.25 are boys (divide 1 by 4)

5. The Parts and Terms of a Proportion

6. Testing Proportions
• Cross products are used to test whether two
ratios are equal and form a proportion.
• Cross products are determined by simply cross-
multiplying a given pair of ratios.
• An equal (=) or not equal sign (≠) is used to
correspond with whether or not the products are
equal or are a proportion.

7. Examples

8. Finding Missing Terms in a
Proportion

9. Word Problems Using Proportions

10. Proportion Quiz

11. Proportion Quiz Answers

12. Summary
• A proportion exists when two ratios are equal.
Whether a pair of ratios is equal or not equal is
determined by multiplying extremes by means or
cross-multiplying the given set of fractions.
Cross products and other methods are also
used to solve word problems using proportions,
and generally to find a missing term in a
proportion.

13. Resources
Online Math Assistance
• Visit www.math.com or www.mathisfun.com for
assistance with proportions and other math problems.
Typing Equations
1. To type an equation in PowerPoint (or Microsoft Word) click the
“Insert” tab at the top of the screen and then the “Equation”
icon.
2. Type what you would like to be converted into a proper
equation into the equation box (type the forward slash /
between the numbers, without spaces, to get a proper fraction).
3. Click enter.
Typing Mathematical Symbols
• To type mathematical symbols, like the “not equal to” sign (≠), etc.,
click the “Insert” tab and then “Symbol” to select the appropriate symbol.
Click insert.