They are both very similar. The 7.5 in both of them stand for the amt. of hydrocodone and oxycodone in each tablet. The 500 and 325 stand for how much acetaminophen or also known as Tylenol is in each tablet. They hydro and oxy are similar except that hydro is made with a process of water and oxy are made with a process of oxygen.
5500mg
5500mg = 5.5g
1000mg =1gram 5500mg =5.5grams
2 more days at most
1 gram = 1000 milligrams. You now have all the information required to work out, for yourself, the answer to this and similar questions. 5500mg=5.5g (1000mg=1g)