A carnival has a duck-pond booth. You choose a rubber duck at random. The mark on the bottom of the duck tells you whether you won a small, medium, or large prize, or no prize at all. There are 70 ducks floating in the pond. There are 6 ducks marked as large-prize winners, 12 ducks marked as medium-prize winners, and 19 ducks marked as small-prize winners. Find the theoretical probability of winning a large prize at the duck pond. Express your answer as a percent. If necessary, round your answer to the nearest thousandth.
8.571%
1166.667%
91.429%
52.857%