Final answer:
Jack is of median height if he is in the 50th percentile, as it indicates he is taller than or as tall as 50% of his peers, which is the definition of the median.
Step-by-step explanation:
True, Jack is of median height if he is in the 50th percentile. The 50th percentile for height indicates that Jack is taller than or as tall as 50% of his peers, which is the definition of median in a given data set. This statistical measure of central tendency is a common way to describe the average or typical value within a range of data. Therefore, being in the 50th percentile for height means that he is of median height.