Question

Write a function declaration and a function definition for a function that takes one argument of type int and one argument of type double, and that returns a value of type double that is the average of the two arguments

Short answer

Question: Write a function in C++ that takes one integer argument and one double argument, and returns the average of the two arguments as a double. Explain the function declaration and definition. Answer: The following function declares and defines a function called `average` that takes an integer and a double as arguments and returns their average as a double. ```cpp // Function declaration double average(int a, double b); // Function definition double average(int a, double b) { double sum = a + b; double avg = sum / 2; return avg; } ``` The function declaration specifies the return type (double), the function name (average), and its arguments' types (int and double). The function definition calculates the average of the two arguments by first adding the integer and double, creating a double result. Then, it divides the sum by 2 and returns the calculated average value, which is a double.

Step-by-step solution

Declare the function

First, we need to declare our function. The declaration should include the return type (double), the function name, and the types of its arguments (int and double). We can call our function "average". ```cpp double average(int a, double b); ```

Define the function

Now that we have declared our function, we need to provide the definition for it. The definition should include the function name, the types of its arguments, and the calculation of the average of the two arguments. ```cpp double average(int a, double b) { double sum = a + b; double avg = sum / 2; return avg; } ```

Explanation of the function definition

In the function definition, we first calculate the sum of the integer and double arguments. Since one of the arguments is a double, the result will also be a double. Afterwards, we divide the sum by 2 to find the average. Finally, we return the calculated average, which is of type double. Here is the final code for the function declaration and definition: ```cpp // Function declaration double average(int a, double b); // Function definition double average(int a, double b) { double sum = a + b; double avg = sum / 2; return avg; } ``` Now you can call this function with an integer and a double argument, and it will return the average of the two as a double.