In this case, we'll have to carry out several steps to find the solution.
Step 01:
Data:
total articles = 12
editorials = 5
P (editorial) = ?
Step 02:
articles selected = 1
P (event) = favorable outcomes / total outcomes
P (editorial) = 5 / 12 = 0.4167
The answer is:
P (editorial) = 0.4167