Do the problem little by little:
First, -20/48 reduces to -5/12.
Next, (t^5) / (t^7) simplifies to 1 / (t^2).
Same with u^2 / u^4: 1 / u^2
v^3 / v^1 = v^2
Let's put the factors back together:
-5 * v^2
--------------------------
12 * u^2 * t^2
-5 v
This could be left as is, or shortened: ----- * [ ------- ]^2
12 t*u
