Question 1099391
He might be correct, but 19 is a teenager as well, and it is not known how many 19 year-olds go, only the 19-30 group.
Aside from statistics, he is implying that while most of the people are over the age of 18, the fact is that 60% are under 30.
On the other hand, there are a relatively small number of children, since child may be defined differently for different people.