Are the following simplified fractions?

1.1/2
2.1/5
3.2/3
4.5/6
5.3/4
6.4/8,1/2

If 4/8 is meant to simplify to 1/2, so yes, they are all simplified.

If 4/8 and 1/2 are separate, then no, because 4/8 simplifies to 1/2.