It depends on the situation and how well you know them.
If you know them well, you can use their first name. Otherwise use their last name preceded by Mr. or Miss.If you don't know their names. young man or young lady will work for a one person. Ladies or gentlemen for several people.
As of October 2019, you'd be 1007 years old ... and likely have a lot of interesting stories to tell.
Septuagenarian
A sexegenarian.
centenarian
You can call anyone who has lived 100 years a Centenarian.
septa-centenarian
Young Adult
They would be seventy years old.
37.6 years total 35.8 years male 39.5 years female
A 90 year old is called an nonagenarian. Nonagenarian are people who are over the age of 90 years old.
an adult or a 25 year old. it really depends on what the sentence is
A person who is 70 years old is commonly referred to as septuagenarian, while someone between 70-79 years old is considered to be in their seventies.