How to Cross-Simplify

By Stefan Robert

Cross-simplifying is a great way to make certain types of equations a whole lot easier to solve. Learn how to cross-simplify with help from an expert in computers, with two degrees in both Computer Science and Applied Mathematics in this free video clip.


Hi, my name is Stefan. Today, I'm going to be speaking on how to cross simplify. Now let's say we are multiplying the two fractions 6/7 x 5/8. We can cross simplify by saying well, 2 goes into 6 3 times and 2 goes into 8 4 times and cross simplify and get 15/28 and the reason being is it's like we are taking out the fraction of 1. So if I rewrote the original fractions, 6/7 x 5/8 that's 2 x 3/7 x 5/2 x 4 which gives me 2/2 x 3/7 x 5/4 and we know this just equals 1 and thus we get the answer 15/28 and that's how you cross simplify.