Answer
$3,550$ students
Work Step by Step
"Over the age of $19$" includes anyone aged $20$ or older.
The population aged 20 or older is the sum of the populations aged $20-24, 25-34,$ and $35$ and older.
Add the percentages represented by these age groups to obtain:
$$43 + 16 + 12 = 71$$
Thus, $71$ percent ot the students are older than $19$.
Hence, In a random sample of $5000$ students, $71\%$ of them are expected to be older than $19$.
$=5000 \left(71/100\right)$
$=50\cdot71$
$=3550$
