This poster demonstrates adding fractions by the "a/b + c/d = (ad + bc)/bd" method. This "crisscross" method to add (and subtract) fractions is a lot less cumbersome than finding the lowest common denominator. In this download you will receive the poster seen in the thumbnail as well as one without a border.
To covert this file to a poster for free: How to Enlarge a File to a Poster!
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