#Format : LIMIT s-1, t - (s - 1)
SELECT ROUND(ABS(x1 - x2) + ABS(y1 - y2), 4)
	FROM (SELECT MIN(lon) x1,  MAX(lon) x2 
			FROM (SELECT*FROM citytable
				WHERE lat < 121.8 ORDER BY lat DESC LIMIT 3, 15) AS Table1) AS latTable,
		 (SELECT MIN(lat) y1, MAX(lat) y2
			FROM (SELECT*FROM citytable
				WHERE lon > 25.1 ORDER BY lon ASC LIMIT 3, 15) AS Table2) AS lonTable;