This is a smartboard activity that I created that practices using all 3 methods of finding missing sides on similar shapes (using ratios, using scale factors, and using proportions). This game also includes solving proportions, writing ratios, finding scale factors, and finding the new perimeter or area of similar shapes based on the scale factor. If you look at the preview you will see an example of each problem... there are 30 total. The first slide is all the possible answers in the game... I give the students a blank bingo card and have them fill in 24 answers from the screen and a free space. I will print out a screen shot of the first screen for myseld and use that to keep track of the answers that were used as we go through the game screen by screen.