Which one will replace the question mark?

and 6 x 9 x 7 = 378

Therefore 5 x 7 x ? = 315

? = 9.

(16 + 24 + 40)/10 = 8

Similarly, (45 + 18 + 27)/10 = 9.

and (6 x 4) + 5 = 29

Therefore, (7 x 5) + 6 = 41

and (4 x 9) = 36 and (2 x 9) = 18

Therefore (9 x 6) = 54 and (4 x 6) = 24.

Therefore, (2)² = 4.

(4 x 3) + 7 = 19

(5 x ?) + 6 = 31

? = 5.

and (7 x 5) + 3 = 38

Therefore (3 x 5) + 3 = 18.

and (32 x 16)/4 = 128

Therefore, (24 x 14)/? = 112

(336/?) = 112

? = (336/112)

? = 3.

(28 - 12) + (16 - 20) = 12

Similarly, (23 -11) + (15- 16) = 11.