Answer:
0.0025 = 0.25%
Step-by-step explanation:
First we need to find how many people don't have flue shots.
28% of 50 is equal to 0.28 * 50 = 14 people.
If 14 people have flue shots, we have 50 - 14 = 36 people that don't have flue shots.
Now, to solve this problem, the probability will be the cases where we have a group of people that don't have flue shots (that is, a combination of 36 choose 15) over the total cases (combination of 50 choose 15):
C(36,15) / C(50,15) = (36!/15!*21!) / (50!/15!*35!) = 0.0025 = 0.25%