Assuming average men, no weapons, and fight until the last man standing. The 100 men would easily win. A pack of hyenas can kill a male lion. You can tire out

Assuming average men, no weapons, and fight until the last man standing. The 100 men would easily win. A pack of hyenas can kill a male lion. You can tire out the Gorilla by pretending to strike, then pull back. Once the Gorilla is too tired, it's over. Humans naturally have higher stamina. Multiply that by 100.