Mathematics, known as the "queen of science", has been playing a decisive role in the expansion of science and technology for a long time. With the diversified development of society, the application of mathematics is more extensive. However, in mathematics class, generally only the explanation of definition, the proof of theorem and the solution of proposition are emphasized, while the need to understand mathematics from life experience is ignored. According to the middle school mathematics curriculum outline, this book fills the gap between mathematics theory and life application through 80 life examples, so that students can understand and appreciate the significance and role of mathematics in life. In daily life, we can actually use mathematical methods to understand things around us, and we can also use the materials of life to strengthen our understanding of mathematical concepts, so that mathematical knowledge can be injected into the atmosphere of life. For example, how to understand why women love to wear high heels? How to learn functions with an ordinary T-shirt? How to master newspapers ..