The assorted cookies is a problem. It would mean more than two types, but only two types of cookies are mentioned in the problem. If we take only these two cookies into account the problem would be solved in this way:
5/8Peanut butter + 160Chocolate chip = Total cookies,
P= peanut butter, C= Chocolate chip,T= total cookies
1T-5/8P = 3/5C, 3/5 = 160 1/5=53.3
hence.. 160C+266.5P= 426.5T