Answer:
0.2917 = 29.17% probability that a randomly selected female student on campus will have served a mission.
Explanation:
A probability is the number of desired outcomes divided by the number of total outcomes.
In this question:
1200 female students, out of them, 350 have served a mission. So
0.2917 = 29.17% probability that a randomly selected female student on campus will have served a mission.