i beleive the oldest person ever alive was 120 something
people generally dont live any longer than that, and even so, reaching 100 years old is pretty uncommon compared to everyone elses life expectancy. the averages for life expectancy also vary in different countries, sometimes drastically.
The average is different in every location....in Tibet (I think), it's quite high...like a lot of people live to 100 or more.
Are you asking about people individually, or the entire human race? You need to be more specific with your questions.
only about 3