Your answer is 6% of x.
We can write the given information as equations to find the answer:
Another way to write "20% of x" is to write 0.2x, so therefore 0.2x = y
You can also write "30% of y" as 0.3y, so 0.3y = z
Now we can substitute in the first equation to the second equation, as we know what y equals in terms of x:
0.3(0.2x) = z
Multiplying out we get:
0.06x = z, and 0.06 as a percentage is 6%
I hope this helps!