To find the probability that 3 people are from Town A and 2 people are from Town B, we can follow these steps:
Step 1: Calculate the total number of ways to select 5 people from the total of 8 people from Town A, 7 people from Town B, and 5 people from Town C. This can be done using combinations:
C(8, 3) * C(7, 2) * C(5, 0) = (8! / (3!(8-3)!)) * (7! / (2!(7-2)!)) * (5! / (0!(5-0)!))
Step 2: Calculate the total number of ways to select any 5 people from the total 20 attendees (8 from Town A, 7 from Town B, and 5 from Town C):
C(20, 5) = 20! / (5! * (20-5)!)
Step 3: Divide the number of ways to select 3 people from Town A and 2 people from Town B by the total number of ways to select any 5 people from the total attendees:
P = (C(8, 3) * C(7, 2) * C(5, 0)) / C(20, 5)
Now you can substitute the values and calculate the probability P.