It depends on how wide the fabric is, but most are around 44" (I think

) so 36"x44" would get you 4 x5 in terms of how many 8"x8" wipes you could fit, so 20 wipes out of one yard. That is assuming you are just serging/overcasting the edges and don't need a seam allowance (which would be a pain to do for a bunch of wipes IMO). There would be a little leftover, but not enough for another row of full 8x8 wipes.
But if you get two continuous yards you could get 9x5=45 wipes out of 2 yards.
(assuming my quickie math is right!)
ETA: I think a yard and a 1/4 (continuous) would get you 25 wipes...