Schwarzenegger's goal was to become the greatest bodybuilder in the world, which meant becoming Mr. Olympia. His first attempt was in 1969, when he lost to three-time champion Sergio Oliva. However, Schwarzenegger came back in 1970 and won the competition, making him the youngest ever Mr. Olympia at the age of 23, a record he still holds to this day.

Answer this question, if possible (if impossible, reply "unanswerable"): How old was Schwarzenegger when he won Mr. Olympia in 1970?
23