Complete the following equation.
12 ( / ) = 4
12 (4/12)= 4
18/3
6
8 ( / ) = 80
19/4
4 3/4
A ( / ) = B
A ( B/A ) = B
36/5
7 1/5
C ( / ) = D
C (D/C) = D
82/9
9 1/9
58 ( / ) = 9
58 (9/58) = 9
72/8
9