Talk:Armor penetration/@comment-24248596-20160207153831/@comment-11815987-20160208104719

For the most part the math is just about right, however Precision is based on champion level not summoner level. It only gives 8.4 armor pen at level 18, and runes give 19.2 with that current set up you would be hitting them as if they had 77.4 armor.

((200* .7)* .75) - 27.6 = 77.4