I've been working my way through 'Learning to Program,' by Chris Pine, to begin to understand both Ruby and the general concepts of programming. Anyway, the little program I've written accomplishes a simple task: it asks for your favorite number, adds one to it, then returns it to you. Here it is:

Code Ruby:
puts 'Hey there, I\'m Uno.'
puts 'What\'s your favorite number?'
number = gets.chomp
better = number.to_i + 1
puts better + '...That\'s better.'
For some reason, I get an error (in terminal) that says :'String can't be coerced into Fixnum (TypeError).' Why can't this variable--which contains a numeric string--be converted into an integer?