The ratios are .
(Write the proportion)
(Form cross products)
(Multiply: )
The ratios form a proportion.
![\"\"](\"http://www.mathskey.com/userfiles/image/steps_images/step1.JPG\")
![\"\"](\"/test/fckeditor/editor/plugins/fckeditor_wiris/integration/showimage.php?formula=81f42fd4f9acb6c3c3b7a6f206bc7800.png\")
.![\"\"](\"/test/fckeditor/editor/plugins/fckeditor_wiris/integration/showimage.php?formula=f4031f5feb3e5dc038d8ed3614b7e802.png\")
(Write the proportion) ![\"\"](\"/test/fckeditor/editor/plugins/fckeditor_wiris/integration/showimage.php?formula=b53b305d2a8db416a8b1d26d756c4323.png\")
(Form cross products) ![\"\"](\"/test/fckeditor/editor/plugins/fckeditor_wiris/integration/showimage.php?formula=21e1125612d7c17a7dbc09dbca5d71bf.png\")
(Multiply: ![\"\"](\"/test/fckeditor/editor/plugins/fckeditor_wiris/integration/showimage.php?formula=b22c2951a76d7d7a8077e32f186fb227.png\")
)![\"\"](\"http://www.mathskey.com/userfiles/image/steps_images/solution.JPG\")