two simple questions.

in english please o.o

Your damage is, basically, INT * M.ATT (with all sorts of confusing factors thrown in, but we can ignore them for this discussion).
Same as a sin's damage is, basically, LUK * W.ATT.

That means there is no one set conversion factor.
If you have, say, 100 total m.att and 500 total int, then to increase your damage 1% you need to get either 1 more m.att or 5 more int. So one might say that for you, 1 m.att = 5 int. However, if you had 100 m.att and 400 int, then to add 1% damage you only need 4 more int, so 1 m.att = 4 int.

Bottom line, to know how many int is one m.att, just divide one by the other. A bit tricky because you don't see your total m.att stat anywhere, you need to add by yourself all the m.att on your gear, your passive skills (mastery, Blessing of the Fairy), and whatever buffs you normally use (Bless/Meditate, m.att potions).