For this you have to use the copy dot flop technique.
First when you have 3 eighths/ 2, you are basically saying 2/1
3 2
--- / ---
8 1
Using this, now you do the copy dot flop. It it goes to 3/8 * 1/2
Copy: Copy the first number exactly
Dot: Change the division sign to a multiplication
Flop: Switch the numerator and the denominator of the second number.
Now do it like you would any problem
3 1 3
--- / --- = ---
8 2 16
Then you can leave it like that, simplify, or mixed number. You cannot do anything to this problem. So your answer is:
3/16