Objective

Students will solve proportions Chapter 8, lesson 2 (8-2).

Vocabulary:

Proportion Cross products

Steps:

To determine whether each pair of ratios form a proportion you must do the following:

* Cross multiply (N with D).

* If products are =, they form a

proportion.

* Write final answer after showing

all work.

Example:

2/13 , 4/26 (problem)

13 x 4 = 26 x 2 (cross X)

52 = 52 (look at answers)

yes, it forms a proportion

Steps continued:

To solve each proportion, you must do the following:

* Cross multiply (N with D)

* Solve for the variable (letter) by

dividing both sides by the # in

front of the letter.

* Write the final answer as Z =

(letter = answer).

Example:

5/9 = w/54 (problem)

9 x W = 54 x 5 (cross M)

9W = 270

9w/9 = 270/9 (divide both sides by 9)

W = 30 (answer)