Breeding probability question?

[Zalvion]

So i'm trying to breed a brave honedge with perfect ivs in attack, def, special def and hp. i wont be using special attack and i dont care what the speed is because going second is better if im using shadow claw or if i go with shadow tag it's priority.

The current parents are a ditto with 6 perfect ivs holding destiny knot and a brave honedge holding everstone and has three perfect ivs hp, atk, sp atk.

So far when i check the off spring of the 50 i've bred so far they all have 3 or less perfect ivs and so far among the ones with 3 ivs none were in a more favorable combination then hp, attack and sp attack.

What is the probability of me getting a honedge with 4 or 5 perfect ivs with these parents.

I would think it would be 6 perfect ivs + 3 perfect ivs/12

so 9/12 chance that a perfect iv gets picked by destiny knot then raise that to the 4th power for 4 perfect ivs and to the 5th for 5 perfect ivs

(9/12)^4 getting me a 31.64% chance

(9/12)^5 getting me a 23.73% chance

is my math wrong i'm not that great at probability.

Also is it guranteed that the destiny knot will pass on 5 ivs from the parents or is it up to 5 of the parents ivs will be passed on?

any help is appreciated.

[Kaphotics]

http://destinyknot.tk/

[Zalvion]

Turns out i didn't have the destiny knot on my ditto, oops anyways every thing worked out now that i fixed it. i now have 3 honedges with 31 ivs in everything but speed. you can lock this thread