element conversion and double dip

[floatAcean]

i'm looking at making a paradox mage,
one of the sustains converts 45% dmg into phys (with adept). But i noticed most gear gives you +temp/+phys dmg. so if I cast a spell that deals 100 temp dmg, and I have +50%temp and +50%phys dmg, how much damage am i dealing?

does 55% of it scale off the +temp dmg, then 45% scale off both (because was temp, now its phys, so it goes through both).

or

55% scales off +temp dmg, 45% scales off +phys dmg.

cheers