Objectives

• Define and call functions that take parameters.
• Define and call functions that return values.
• Use both to make functions reusable and flexible.
• Differentiate between parameters and arguments.

Activity Tasks

• Create a new JavaScript file named 3-2-parameters.js.
• Complete each task and test your program output after every function is added.

Task 1: Passing Data into a Function

• Create a function named greetUser(name) that prints a personalized greeting.
• Prompt the user for their name and call the function, passing the input as an argument.

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function greetUser(name) {
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  console.log("Hello, " + name + "!");
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  console.log("Welcome to the Math Utility Program.");
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  console.log();
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}
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console.log("--- Math Utilities ---");
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let userName = prompt("Enter your name: ");
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greetUser(userName);

Task 2: Returning a Value from a Function

• Define a function square(n) that returns the square of a number.
• Ask the user for a number, call square(num), and print the result.

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function greetUser(name) {
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  console.log("Hello, " + name + "!");
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  console.log("Welcome to the Math Utility Program.");
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  console.log();
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}
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function square(n) {
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  return n * n;
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}
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console.log("--- Math Utilities ---");
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let userName = prompt("Enter your name: ");
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greetUser(userName);
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let num = parseInt(prompt("Enter a number to square: "));
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let result = square(num);
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console.log("The square is " + result);
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console.log();

Task 3: Combining Parameters and Return Values

• Create a function average(a, b) that returns the average of two numbers.
• Add another function randomInRange(min, max) to return a random integer between two values.
• Test both functions by prompting the user for input and displaying the results.

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function greetUser(name) {
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  console.log("Hello, " + name + "!");
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  console.log("Welcome to the Math Utility Program.");
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  console.log();
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}
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function square(n) {
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  return n * n;
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}
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function average(a, b) {
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  return (a + b) / 2;
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}
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function randomInRange(min, max) {
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  return Math.floor(Math.random() * (max - min + 1)) + min;
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}
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console.log("--- Math Utilities ---");
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let userName = prompt("Enter your name: ");
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greetUser(userName);
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let num = parseInt(prompt("Enter a number to square: "));
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let result = square(num);
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console.log("The square is " + result);
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console.log();
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let a = parseFloat(prompt("Enter first number: "));
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let b = parseFloat(prompt("Enter second number: "));
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let avg = average(a, b);
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console.log("The average is " + avg);
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console.log();
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let min = parseInt(prompt("Enter minimum value: "));
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let max = parseInt(prompt("Enter maximum value: "));
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let random = randomInRange(min, max);
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console.log("Random number between " + min + " and " + max + ": " + random);

Sample Output

Your program output should look similar to the example below.

Enter your name: Anthony
Hello, Anthony!
Welcome to the Math Utility Program.

Enter a number to square: 6
The square is 36

Enter first number: 8
Enter second number: 10
The average is 9

Enter minimum value: 1
Enter maximum value: 10
Random number between 1 and 10: 4

Reflection Questions

You may write your reflection answers as comments at the bottom of your code.

1. What is the difference between a parameter and an argument?
2. Why does a function that sends back a result need a return statement?
3. How could one function's return value be used as input to another function?
4. Why is using parameters and returns more flexible than relying on global variables?

Submission

Submit your completed .js file and reflection answers to the appropriate dropbox.

Activity Complete