Pitchersssss.rb

class Pitcher
  attr_accessor :whip, :age
  alias :whip_1 :whip
  
  (2..20).each do |num|
    define_method("whip_#{num}") do
      if self.age < 28
        eval("self.whip_#{num-1}") * 0.95
      else
        eval("self.whip_#{num-1}") * 1.05
      end
    end
  end
  
end

run.rb

@pitcher = Pitcher.new
@pitcher.whip, @pitcher.age = 1, 32

(1..20).each do |num|
  result = eval("@pitcher.whip_#{num}")
  puts "@pitcher.whip_#{num} = #{result}"
end