Surely it's gotta be an away tie. We've had 10 home cup ties in a row, the last away tie was Millwall in the FA Cup Jan 2013. The odds on 11 in a row must be massive.
One in two.
One in two thousand more like
The odds on getting eleven home times in a row is one in 2,048.
However, as we've already had ten in a row the odds on getting an eleventh is, as Paulie states, one in two.