If  '+' means '–', '–' means '÷', '÷' means '×'

226    231     466    ?    5606   28031        

What will come in place of the question mark (?) in the following series?

80, 200, 400, 600, ?, 300

What will come in place of the question mark (?) in the following series?

72, 108, 172, ?, 416, 612

What will come in place of the question mark (?) in the following series?

175, 160, 140, 115, ?

44      45       41      50       ?       59       23

24     12     ?     24   96     768

168, 164, 155, 139, ?, 78

380, ?,  360, 324, 260, 160

196, 196, 203, 229, 292, ?

79, 248, ?,  225, 125, 206