Final answer:
The probability of randomly selecting the 4 oldest people from a group of 7 is 1, or 100%.
Step-by-step explanation:
The group of interest in this question is the 4 oldest people in the group. The size of the group of interest is 4, and the size of the sample is 7.
To calculate the probability, we need to find the number of ways to choose 4 people from the group of 7 and divide it by the total number of possible outcomes, which is the number of ways to choose any 4 people from the group of 7.
There are 7 choose 4 ways to choose 4 people from the group of 7, which can be calculated as:
C(7,4) = 7! / (4! * (7-4)!) = 35
The total number of possible outcomes is 7 choose 4 as well, since we are choosing any 4 people from the group of 7. So the probability is:
Probability = Number of favorable outcomes / Total number of possible outcomes = 35 / 35 = 1
Therefore, the probability that the 4 randomly selected people are the 4 oldest in the group is 1, or 100%.