Answer:
Collectively, the total sample took 9000 course credits.
Step-by-step explanation:
The mean number of course credits taken is the total number of credits which the sample took collectively divided by the size of sample. Mathematically
[tex]M = \frac{T}{N}[/tex]
In which
M is the mean number of course credits taken
T is the total number of course credits taken
N is the size of the sample.
In this problem, we have that:
[tex]M = 18, N = 500[/tex]
We have to find T. So
[tex]M = \frac{T}{N}[/tex]
[tex]18 = \frac{T}{500}[/tex]
[tex]T = 500*18[/tex]
[tex]T = 9000[/tex]
Collectively, the total sample took 9000 course credits.