16.  33, 48, 65, 84, ? , ?

17.  120, 440, 960, 1680, ?

18.  QRE, RSD, STC, ?

19.  BMX, DNW, FOU, ?

20.  D, H, L, R, ?

21.  2, 3, 5, 6, ?, 9, ?, 12

22.  3, 15, 4, 16, 5, 17, 6, ? , 7

23.  BEAG, DGCI, FIEK, ?

24.  Direction: Which one set of letters when sequentially placed at the gaps in the given letters series shall complete . b _ t _ a _ _ add _ dbaad

25.  2, 3, 5, 6, 7, 9, 10, 11, 13, ?

26.  81, 192,375, ?,1029

27.  Direction: Find the wrong number in the following series : 216, 163, 120, 72, 24

28.  12-5, 80, 45, 20, ?

29.  Direction: Which one set of letters when sequentially placed at the gaps in the given letters series shall complete . -tu-rt-s-us rtu-

30.  PON, RQP, TSR, VUT, ?