# Exercises: Methods

In order to learn in practice what we have learned about methods we will solve a few problems, in which it will be required to write methods with certain functionality and after that to invoke them by passing them data, read from the console.

## What We Learned in This Chapter?

Before starting, let's review what we have learned about the methods in C#:

• We learned that the purpose of methods is to split big programs with a lot of lines of code into smaller, shorter tasks.
• We introduced ourselves with the structure of methods, how to declare them and invoke them by their name.
• We went over examples for methods with parameters and how to use them in our program.
• We learned what signature and return value of a method is and also what is the purpose of the operator return.
• We introduced ourselves with the good practice when working with methods, how to name them and their parameters, how to format code, etc.

### Defining a Method

This is how we define a method, which takes a parameter and returns a value:

static double CircleArea(double radius)
{
}


### Invoking a Method

This is how we invoke a method, pass a parameter value (argument) for the invocation and process the returned value:

Console.WriteLine("a = {0}, area = {1}", 5.33, CircleArea(5.33));
// a = 5.33, area = 89.2491915365671

Console.WriteLine("a = {0}, area = {1}", 9.999, CircleArea(9.999));
// a = 9.999, area = 314.0964366475


## The Exercises

We will work on the following exercises: