coding_your_code.rb

def calculate(size,num_colours)
  colour_price = 10
  colour_price = 15 if num_colours > 2
  total = ((size * 15) + (num_colours * colour_price)) * 1.15
  total_in_currency = "%05.2f" % total
  puts "Your total is $#{total_in_currency}"
end

# Enter size of sign, and number of colours as parameters
calculate(10,3)