I'm guessing you mean (1/3)³ * (3/2)³
You can rewrite this like this
1³ x 3³
---------
3³ * 2³
1³=1 and 3³=27
27 times 1 is 27 so we get 27 on top as the numerator.
27
---
3³ * 2³
on the bottom, 3³=27 and 2³=8
27 times 8 is 216 on the bottom
27/216
Then we just need to reduce the fraction. We can find the greatest common factor of 27 and 216 which in this case is 27
27/27 1
-------- = ----
216/27 8
1/8