I'll bet any amount you want that when Arsenal's accounts for this season come out, you wouldn't have reduced your wage bill by £20m.
Do you honestly believe that Pepe, your record signing by a distance, is joining you for much less (if at all) than what your highest earners are on? Tierney, Ceballos and Luiz will all be earning £100k+ per week too. I have no idea who this Martinelli guy is but the 4 other signings alone will account for at least £30m in wages. Reports in Italy, unsurprisingly, are that you're paying a chunk of Mikhi's wages and I'm certain you'll be paying most if not all of Saliba's wages while he's at St Etienne too. There will no doubt be clauses in deals (and or new deals) for certain youngsters that have broken into the first team and new deals to various senior players - there's already reports of new deals for Auba and Laca on the cards.