Answer:
Pr(3worker's comp cases and 4 Medicare patients) = 0.37879
Step-by-step explanation:
Number of worker’s comp cases = 6
Number of Medicare patients = 6
Total number of people = 6 + 6 = 12
Total number of ways of selecting 7 people from 12 people = 12C7
Total number of ways of selecting 7 people from 12 people = 
Total number of ways of selecting 7 people from 12 people = 792 ways
Number of ways of selecting 3 worker's comp cases = 6C3
Number of ways of selecting 3 worker's comp cases = 
Number of ways of selecting 3 worker's comp cases = 20 ways
Number of ways of selecting 4 Medicare patients= 6C4
Number of ways of selecting 4 Medicare patients = 
Number of ways of selecting 4 Medicare patients = 15 ways
Pr(3worker's comp cases and 4 Medicare patients) = (15*20)/792
Pr(3worker's comp cases and 4 Medicare patients) = 300/792
Pr(3worker's comp cases and 4 Medicare patients) = 0.37879