Activate/DeActivate Silent and general mode on the basis of location in services

i have saved a number of lat lng value in sqlite data base and i am comparing it with current latlng value and calculate its distance if the distance between two points less then 20 meters then activate silent mode else activate general now i am facing the problem at the point when it comparing current location with all number of sq-lite value. for the first time let suppose at position[0] the calculated value is less then 20 then the silent mode will activated after that at position[3] in the same loop the calculated value is greater then 20 meters again general mode will activated . how can i solve this problem any help Thanks