The answer to your question is the probability to select a yogurt of raspberry is 1/4 or 25%.
Explanation:
Data
Number of cartons = 12
Number of cartons of raspberry = 3
To solve this problem, just use the formula of probability and simplify it to get the result.
Formula
P(A) =
Substitution
P(A) = 3/12
Simplification
P(A) = 1/4 or 25%