Mathematics (math) has been defined as:
The study of the measurement, properties, and relationships of quantities and sets, using numbers and symbols.
Therefore, any computation or calculation that needs to be done in any subject requires the use of mathematics.
Chemistry uses mathematics to set up and solve complex equations in determining how certain elements are going to affect each other, how certain elements will change, or how certain elements react to each other. In Physics, formulas are used to determine force, speed, mass, energy, and many other characteristics of objects. In cooking or sewing classes, ingredient quantities have to be decreased or increased, requiring a knowledge of basic mathematical principles. In shop classes, mathematics is required to know how much material is to be used in a project, how much force is to be used to move something, or how full to fill things. In geography, history, and science math helps us figure out how long something lived, how long it is between events, how long something lasted, or how old something is.
So, you can see that math is used everywhere by everybody every day, especially in schools.