SO, just in general, I'm having difficulty telling the difference between chromosomes, chromatids, sister chromatids, Homologous pairs, n and 2n. But I would really appreciate it if someone could explain how to get the answer for the question below. My initial thought was that there would still be 20... but the back of the book said that was wrong. It was a MC with none of the above as the answer so I was thoroughly confused. 

If a diploid cell with 20 homologous pairs completed meiosis and cytokinesis, each cell formed would contain _____ homologous pairs. 

Oh I was thinking of mitosis, whoops, would the answer be 0? I got that from looking at an example problem, so I'm not completely sure why there would be 0

I feel like I'm talking my self through this at this point, but please correct me if I'm wrong. So during meiosis, the division nd replication results in 1 of each origional "type" of chromosome in each new cell so there are no Homologous pairs because no chromosomes "match" each other. 

Typically the confusion is based on difficulty in grasping the different units that are at play here. You should draw out a chromsome, and label the chromatids on it. That draw a sister chromomes and do the same. What are the key steps in meiosis? What do yo end up after the first, and what after the second? I think you kind of get it, but the way you describe it is slightly confused.

Going from memory, the question is about production of gametes for sexual reproduction, so the answer would be 10 pairs, as an egg or sperm ready for fertilisation. 

Unless it's a trick question.

Look, you should find and read "Chromosome Biology". Here is how it looks: