My brother and I inherited a home in 2015 and sold in 2016; proceeds were 50/50; when it asks for FMV do I do it 50/50 as well?

Yes, you will use 50% of the fair market value (FMV) of the inherited property as your basis in the property.

Your brother will use the other 50% as his basis.

Do make sure that you also include 50% of all the selling costs paid , as well as your share of any expenses to maintain or improve the property that have not already been claimed by the estate (if this applies).