He placed ping pong balls numbered from zero to 32, so I guess that would be, what, 33 ping pong balls, in a drum and mixed them well. Note that the median of the population is 16, right? The median number, of course, yes, and that population is 16. He then took a random sample of five balls and calculated the median of the sample. So we have this population of balls. He takes a, we know the population parameter. We know that the population median is 16, but then he starts taking a sample of five balls, so n equals five, and he calculates a sample median.