This document provides examples and explanations of percentage calculations and tricks. It begins by defining key terms like numbers, ratios, fractions, and percentages. It then provides 21 example problems demonstrating how to use percentages to solve word problems involving topics like profit/loss, population changes, exam scores, and more. The examples illustrate common percentage calculation methods and tricks like breaking percentages into fractions. The document emphasizes learning fractions and tables to help solve percentage problems more quickly.