Answer: the number of cephalopods in her seashells collection is 26.
Explanation:
Maria has a collection of 64 seashells consisting of three types bivalves,gastropods,and cephalopods. If 1/4 of her collection are bivalves, it means that the number of bivalves that she has is
1/4 × 64 = 14
If 3/8 of her collection are gastropods, it means that the number of gastropods in her collection is
3/8 × 64 = 24
Therefore, the number of cephalopods in her seashells collection is
64 - (14 + 24) = 26