In mathematics, "Numerical and Algebraic Expressions" are fundamental concepts that help understand and perform various calculations, expressing numbers and variables through mathematical operations. This topic is important because it forms the basis for solving more complex mathematical problems, as well as developing logical thinking and analytical skills. For example, you are a road construction company estimator. You clearly know how much and what materials are needed to build one kilometer of road, and this is a numerical expression because it involves addition and multiplication, but you cannot know exactly how many kilometers of road will be ordered to be built in the future and what the material costs will be at that time and here we come to algebraic expressions, where "variables" such as x and y, can represent any number, thus expressing more general calculations and relations. Now a little theory. A mathematical statement written with mathematical symbols (numbers, operation signs, etc.) is called a mathematical expression. Mathematical expressions are formed by numbers connected by operation signs, and even a single number can be called a mathematical expression. for example, −51.1x; 10 * 4 - 9; (5 - z) : 8 etc. But there is also a finer division - A mathematical expression in whose record only numbers are used is called a numerical expression, while one in whose record variables (in the form of letters) are also used is called an Algebraic expression. Let's take a closer look! Numerical expressions are those consisting of only numbers, arithmetic operation signs, and parentheses. By performing all the specified operations, the value of the numerical expression is obtained. For example, the expression 2 + 3 * 5 is a numerical expression and by performing the calculation its numerical value is 17. by the way - A numerical expression in which there is division by zero cannot be calculated because division by zero is not possible. On the other hand, Algebraic expressions are those in which variables appear alongside numbers. For example, the expression 100x + 60y is an algebraic expression. If a specific number is placed in place of each variable in the algebraic expression, then a numerical expression is obtained and then the numerical value of the algebraic expression can be calculated. For example, Imagine the daily mileage record of a tourist bus, where 100 is the speed at which it drives outside the city, but 60 kilometers per hour is the speed driving through populated areas. Convert the algebraic expression to numerical and solve the problem if the bus has driven 5 hours outside the city and one hour through populated areas. Here is the correct answer. 100*5+60*1=500+60=560km Learning about "Numerical and Algebraic Expressions", we learn how to perform various mathematical operations with numbers and variables. This helps us understand and perform calculations necessary both in mathematics and in everyday life. Numerical expressions give us a direct calculation of numbers, while algebraic expressions give us a general way to express various situations and solve problems using variables.