You are right . . . There are 8 equivalence classes.Let be the set of all bit strings of length 10.
Let be the relation defined on where two bit strings
are related if the third, fourth and last bits are the same.
a) Show that is an equivalence relation.
(b) Enumerate one bit string from each of the different equivalence classes of .
And they look like this:
And the blanks can be filled with any combination of 0's and 1's.