612
612 / 3 + 3 = 207
207 / 3 + 3 = 72
72 / 3 + 3 = 27
27 / 3 + 3 = 12
12 / 3 + 3 = 7
What will come in place of the x in the following Number series? 612, 207, 72, 27, 12, x

a) 6
b) 7
c) 8
d) 9
e) 10