Reference Topics 6-7

This site gives some practice with ratios.
http://www.purplemath.com/modules/ratio.htm

This site gives some practice with proportions. Scroll down to the bottom and check out the next several pages as well.
http://www.purplemath.com/modules/ratio2.htm

This site gives some examples of working with proportions.
http://www.purplemath.com/modules/ratio2.htm