Select/filter for filtering in Ruby - Mini Project: Build & Apply

Select/filter for filtering

📖 Scenario: You are managing a small bookstore's inventory. You want to find all books that are priced below a certain amount to offer a discount.

🎯 Goal: Build a Ruby program that filters a list of books to find only those priced below a set threshold using the select method.

📋 What You'll Learn

Create a hash called books with these exact entries: 'Ruby Basics' => 25, 'JavaScript Guide' => 40, 'Python 101' => 30, 'HTML & CSS' => 20

Create a variable called max_price and set it to 30

Use select on books to create a new hash called affordable_books containing only books with price less than max_price

Print affordable_books to display the filtered books

💡 Why This Matters

🌍 Real World

Filtering items by price is common in online stores to show discounts or deals.

💼 Career

Understanding how to filter collections is important for data processing and building user-friendly applications.

1

Create the initial books hash

Create a hash called books with these exact entries: 'Ruby Basics' => 25, 'JavaScript Guide' => 40, 'Python 101' => 30, 'HTML & CSS' => 20

Ruby

# Create the books hash with the given entries
# Your code here

Need a hint?

Use curly braces { } to create a hash with keys and values separated by =>

2

Set the maximum price threshold

Create a variable called max_price and set it to 30

Ruby

books = {
  'Ruby Basics' => 25,
  'JavaScript Guide' => 40,
  'Python 101' => 30,
  'HTML & CSS' => 20
}

# Create max_price variable and set it to 30
# Your code here

Need a hint?

Use a simple assignment to create max_price with value 30

3

Filter books priced below max_price

Use select on books to create a new hash called affordable_books containing only books with price less than max_price

Ruby

books = {
  'Ruby Basics' => 25,
  'JavaScript Guide' => 40,
  'Python 101' => 30,
  'HTML & CSS' => 20
}

max_price = 30

# Use select to filter books priced less than max_price
# Your code here

Need a hint?

Use a block with select that checks if price is less than max_price

4

Print the filtered affordable books

Write puts affordable_books to display the filtered books

Ruby

books = {
  'Ruby Basics' => 25,
  'JavaScript Guide' => 40,
  'Python 101' => 30,
  'HTML & CSS' => 20
}

max_price = 30

affordable_books = books.select { |title, price| price < max_price }

# Print affordable_books
# Your code here

Need a hint?

Use puts to print the affordable_books hash