User blog comment:Commander Marko/Razor, The Sharpshooter (Updated!)/@comment-72.14.127.74-20130203205413/@comment-71.100.101.68-20130328205436

I don't know why you mentioned Wit's End, it has nothing to do with Armor Penetration. Besides, % arpen stacks multiplicatively, so with a Last Whisper (hopefully what you meant) you'd get 60% + 35% of 60% (and then likely an extra 8% from masteries, on a good carry mastery set)