These are ratio, unit rate and proportion websites that you may acccess to practice your skills.
http://www.arcademicskillbuilders.com/games/dirt-bike-proportions/dirt-bike-proportions.html
http://www.ixl.com/math/practice/grade-5-ratio-tables
http://www.quia.com/cb/195515.html
http://www.mathsisfun.com/measure/unit-price-game.html