EDIT: Sorry, this post was rambly before - this is my first question and the instructions said to explain exactly what you were doing. I hope it is clear what I was asking now. And I hope it is appropriate to ask for this help (just need a one word answer really).
QUESTION: I have 87 degrees of freedom. I have to look up the critical value in an F-table. It has 60 and 100 for the second degree of freedom. Should I round up, or down, or interpolate?