# File lib/compass/sass_extensions/sprites/layout_methods.rb, line 77
        def calculate_repeat_extra_width!
          require 'rational' #for ruby 1.8.7
          m = @images.inject(1) {|m,img| img.repeat_x? ? m.lcm(img.width) : m}
          remainder = @width % m
          @width += (m - remainder) unless remainder.zero?
        end