What percent of 200 is 0.5?
of 200 is 0.52 I

You're looking for the percent, so your equation would be:

x% × 200 = 0.5

(x/100) × 200 = 0.5

2x = 0.5

x = 0.25

So, 0.25% of 200 is 0.5.

* You can check your work by multiplying 0.25% × 200. Surely enough, it does give you 0.5.

Answer = 0.25%