Operator precedence in Kotlin - Mini Project: Build & Apply

Operator precedence

📖 Scenario: Imagine you are calculating the total cost of items in a shopping cart with discounts and taxes applied. Understanding how Kotlin calculates expressions helps you get the right total.

🎯 Goal: You will write Kotlin code to calculate a total price using multiple operators and see how operator precedence affects the result.

📋 What You'll Learn

Create variables with exact values for item price, discount, and tax rate

Create a variable for the discounted price calculation

Calculate the final price using operator precedence rules

Print the final price

💡 Why This Matters

🌍 Real World

Calculating prices with discounts and taxes is common in shopping apps and billing systems.

💼 Career

Understanding operator precedence helps developers avoid bugs in financial calculations and write clear, correct code.

1

Create initial price variables

Create three variables: itemPrice with value 100, discount with value 20, and taxRate with value 0.08.

Kotlin

// Create variables itemPrice, discount, and taxRate with given values
// Your code here

Need a hint?

Use val to create variables and assign the exact values.

2

Calculate discounted price

Create a variable discountedPrice that subtracts discount from itemPrice using the expression itemPrice - discount.

Kotlin

val itemPrice = 100
val discount = 20
val taxRate = 0.08
// Calculate discountedPrice by subtracting discount from itemPrice
// Your code here

Need a hint?

Use subtraction operator - to find discountedPrice.

3

Calculate final price with tax

Create a variable finalPrice that calculates the total price by adding tax to discountedPrice. Use the expression discountedPrice + discountedPrice * taxRate to apply operator precedence correctly.

Kotlin

val itemPrice = 100
val discount = 20
val taxRate = 0.08
val discountedPrice = itemPrice - discount
// Calculate finalPrice by adding tax to discountedPrice
// Your code here

Need a hint?

Remember multiplication happens before addition without parentheses.

4

Print the final price

Write a println statement to display the value of finalPrice.

Kotlin

val itemPrice = 100
val discount = 20
val taxRate = 0.08
val discountedPrice = itemPrice - discount
val finalPrice = discountedPrice + discountedPrice * taxRate
// Print the finalPrice
// Your code here

Need a hint?

Use println(finalPrice) to show the result.