Calculating Percent of Increase and Decrease

Sheena Doria

This educational video provides a clear, step-by-step guide on how to calculate percent of change, specifically focusing on percent increase and percent decrease. Through the use of an animated teacher avatar and clear on-screen text, the video breaks down the mathematical process into manageable parts: identifying whether a change is an increase or decrease, determining the amount of change, setting up the ratio with the original amount, and converting the resulting decimal into a percentage. The video uses two practical, real-world examples involving price changes—a notebook increasing in price and a pen decreasing in price. These relatable scenarios help ground the abstract mathematical concepts. The narrator deliberately paces the explanation, walking viewers through the subtraction required to find the difference, the setup of the division problem, and the mechanics of moving the decimal point to find the final percentage. For educators, this video serves as an excellent instructional tool for 6th and 7th-grade math classrooms introducing ratios and percentages. It is particularly useful for addressing the common student misconception of dividing by the new amount rather than the original amount. The video's structure allows for a "pause-and-practice" approach, where teachers can stop the video after the problem is presented to let students attempt the calculation before seeing the solution.