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Course Outline

Exercise: Find Discount


We created two variables to store the original price of a product in dollars and the discount percentage applied to that price.

Use these two variables and arithmetic operations to compute and print the discount amount in dollars.


Example:

For example, if price was 150 and discount was 10, the answer would be 15.

Why? Because the discount is 10%. And 10% of 150 dollars is 15 dollars.

Introduction

In this lesson, we will learn how to calculate the discount amount given the original price of a product and the discount percentage. This is a common task in various applications such as e-commerce websites, billing systems, and financial software. Understanding how to perform this calculation is essential for developers working in these domains.

Understanding the Basics

Before diving into the solution, let's understand the basic concepts:

  • Price: The original cost of the product before any discounts.
  • Discount Percentage: The percentage by which the original price is reduced.
  • Discount Amount: The actual amount deducted from the original price.

To calculate the discount amount, we use the formula:

Discount Amount = (Price * Discount Percentage) / 100

This formula helps us determine the portion of the price that is reduced based on the given discount percentage.

Main Concepts

Let's break down the key concepts and techniques involved:

  • Variables: We will use variables to store the price and discount percentage.
  • Arithmetic Operations: We will use multiplication and division to calculate the discount amount.

By applying these concepts, we can easily compute the discount amount.

Examples and Use Cases

Let's look at a few examples to understand how to apply these concepts:

Example 1:

Price: 200
Discount Percentage: 15
Discount Amount = (200 * 15) / 100 = 30

Example 2:

Price: 350
Discount Percentage: 20
Discount Amount = (350 * 20) / 100 = 70

These examples demonstrate how to calculate the discount amount for different prices and discount percentages.

Common Pitfalls and Best Practices

Here are some common mistakes to avoid and best practices to follow:

  • Incorrect Formula: Ensure you use the correct formula to calculate the discount amount.
  • Data Types: Use appropriate data types for price and discount percentage to avoid precision issues.
  • Code Readability: Write clear and readable code with proper variable names and comments.

Advanced Techniques

For more advanced scenarios, you might need to handle additional factors such as:

  • Multiple Discounts: Applying multiple discounts sequentially or cumulatively.
  • Conditional Discounts: Applying discounts based on certain conditions or thresholds.

These techniques can be implemented by extending the basic formula and adding conditional logic.

Code Implementation

Here is the Java code to calculate the discount amount:

public class DiscountCalculator {
    public static void main(String[] args) {
        // Define the price and discount percentage
        double price = 150.0;
        double discountPercentage = 10.0;

        // Calculate the discount amount
        double discountAmount = (price * discountPercentage) / 100;

        // Print the discount amount
        System.out.println("The discount amount is: $" + discountAmount);
    }
}

This code snippet demonstrates how to calculate and print the discount amount using the given price and discount percentage.

Debugging and Testing

To ensure your code works correctly, follow these tips:

  • Print Statements: Use print statements to verify intermediate values and calculations.
  • Test Cases: Write test cases with different prices and discount percentages to validate your code.

Example test case:

Price: 100, Discount Percentage: 5, Expected Discount Amount: 5

Thinking and Problem-Solving Tips

When approaching problems related to discount calculations:

  • Break Down the Problem: Divide the problem into smaller steps, such as reading input, performing calculations, and printing output.
  • Practice: Solve similar problems to improve your understanding and skills.

Conclusion

In this lesson, we covered how to calculate the discount amount given the original price and discount percentage. We discussed the basic concepts, provided examples, and shared best practices. By mastering these concepts, you can handle various discount-related calculations in real-world applications.

Additional Resources

For further reading and practice, check out these resources: