That is true we can not tell for sure who will finish in the fourth position or not but the way it appears now, I think Newcastle stand a chance of finishing at the fourth position that is if they win all there remaining match but I don't think it is possible for them to win the remaining match and considering the fact that football is unpredictable. However, Manchester city and Chelsea are the favorite to finish there but they are not stable in there winning this period but if Newcastle lose their outstanding then Chelsea will still have more advantage.
Actually Newcastle do not really have to win all of their remaining games to be at the fourth position moreover the fifth position currently isn't a bad one and so I don't think they will even have to struggle so hard because finishing at either position still qualifies them for the champions league next season, they don't need that very top four finishing except they are targeting the premier league title which ofcourse is too late to aim at then they will need to win all of their remaining games. Even Manchester City and Chelsea will now have to ease up with the struggle seeing that they can still secure a UCL spot from the fifth position on the table.