Proportions

=__ATTENTION !! WHEREVER YOU MAY SEE A * THAT IS AN EXAMPLE IN MATH DOC. Proportions __=

__//** Example: **//__
Use cross products to find out the porportion 1* is true. 2 x 40 = 7 x 10 80 = 70 -> Write cross products 80 /= 70 > Simplify

__ Use cross products to write and solve equations involving proportions. __
5x = 6 x 25 --> Set cross products equal to each other.
 * EXP. 2* > The cross products are 5x and 6 x 25 or 150.

5x = 150 -> Simplify

*3 ---> Use the Division Property of Equality.

x = 30 --> Simplify

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__Word Problem:__

 * |||| [[image:http://www.algebralab.org/img/5cd22609-4df5-413d-b939-a9c2ef2205f2.gif width="100" height="36"]] ||
 * Sam works as a dental hygienist. Last week Sam made $500 for 20 hours of work. How many hours must Sam work in order to make $700? ||

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