One bought fruits from a store and is mafrish the one percent plus a little more (for Terumah and Trumas maaser). If there is a possibility that SOME of the fruits are revai (the store takes deliveries from different vendors) which is potur from maasros, then the original one percent of the whole is inaccurate and the maasros are mekukalim ?
Let me ask your question a little sharper. If the percent that was taken off was revai then the whole process is invalid. To deal with this question we would really have to know where this store is, what are the chances that they have the same type of fruit from multiple vendors, and what are the possibilities that terumos etc. were already separated.