Challenge 1: Interpolation vs Concatenation — Solution

product = "Wireless Mouse"
price = 24.99

# Interpolation (idiomatic)
puts "The #{product} costs $#{price}."

# Concatenation (works, but clunkier)
puts "The " + product + " costs $" + price.to_s + "."

=begin
Output:
The Wireless Mouse costs $24.99.
The Wireless Mouse costs $24.99.

Notes:
- Both lines print the same sentence, but the concatenation version needs
  price.to_s because + between a String and a Float raises a TypeError —
  Ruby won't silently convert a number to a string the way PHP does.
- The interpolated version handles the to_s conversion automatically inside
  the #{ } braces, which is the main reason it's the idiomatic default.
=end