Input (grade 8): One study found a weak correlation between the size of the stretched penis and foot size and height. Another investigation failed to find any evidence for a link between shoe size and stretched penis size.
Output (grade 9): The arithmetic mean human penis is approximately 12.9 t in length, the circumference is approximately 12.3 c/O. There is no scientific relation between either penis size or race, and shoe size or stretched penis size.