Math in Real Life. That playlist that started out with just a couple dozen lessons has now grown to include 82 lessons. The "real life" context in these lessons isn't things like "how calculating percentages helps you be a frugal shopper." The "real life" context found in the videos in the Math in Real Life series is broad in nature. For example, you will find lessons about how math is used to guide ships and why airlines often sell more seats than they have on an airplane.