A mandatory seat-belt law ends up raising the number of traffic fatalities if it lowers fatalities per accident from 0.05 to 0.03 while raising the number of accidents per period from 30,000 to greater than ___________ accidents per period.

Question

Quizplus · Accepted Answer

Let's call the number of accidents per period after the implementation of the seat-belt law "x".

Before the law, the total number of fatalities would be:

30,000 accidents * 0.05 fatalities per accident = 1,500 fatalities

After the law, the total number of fatalities would be:

x accidents * 0.03 fatalities per accident = 0.03x fatalities

The law is effective if it reduces the total number of fatalities:

1,500 fatalities > 0.03x fatalities

50,000 accidents < x

Therefore, the number of accidents per period must be greater than 50,000 for the law to reduce the total number of fatalities.

A Mandatory Seat-Belt Law Ends Up Raising the Number of Traffic