There's 100 marbles in the bag. And 50 of them involve picking a magenta. So 50 out of 100, and this is the same thing as a 1 half probability. So you could say, well, theoretically, there is a 1 half probability. I just did the math. If you say these are 100 equally likely possibilities, 50 of them are picking magenta. Now let's say you actually start doing the experiment.