macro filter + math question.

so as im no better at math than my 3 year old I am wondering if some genius can help me.....
if I screw a x4 macro filter to my stock 18-55mm lens (on a 600D body) what magnification am I likely to achieve in terms of subject to sensor ratio?....and same question if I were to screw a x10 filter.
many thanks in advance, my head is hurting just thinking about it lolol

If your 3 year old can put the numbers into this
http://www.cambridgein​colour.com …tension-tubes-closeup.htm

thanks for the link mate. i need a strong coffee and pain killers now my head hurts lol but the way my three year old has worked it out it seems like i can get near 1:1 if i have the +4 & +10 on the lens at 55mm.....cool.