On average, a one-bone prime rib gives enough portions for about two people, while a four-bone prime rib gives enough portions for eight to 10 people. A full prime rib consists of the sixth through 12th bones of the cow's ribcage, which feeds 14 to 16 people.
Prime rib has a tender texture because it is a part of the cow's body that does not get much exercise. Some ways to cook a prime rib include grilling, smoking and spit roasting. To serve a prime rib rare, the internal temperature should be at 120 to 125 degrees Fahrenheit, while a medium prime rib should be 130 to 135 degrees Fahrenheit.