Question: how many times a day do you walk past a murderer?
Answer: 10 new people per day * 365 days per year * 71 years of living = about 260,000 separate individuals somebody might walk by. 260,000 people in a lifetime * 6 murderers per 100,000 people = 15.6 or about 16 murderers. Say somebody lives in a big city where they get out all the time and walk by 1000 new people per day.