Violent crime in many American schools is an unfortunate fact of life. An analysis of schools and violent crime yielded the table of joint probabilities shown next.

Violent Crime Committed No Violent Crime Level This Year Committed Primary .393 .191 Middle .176 .010 High School .134 .007 Combined .074 .015

(Source: Statistical Abstract of the United States, 2009, Table 237.)

If one school is randomly selected find the following probabilities.

a. Probability of at least one incident of violent crime during the year in a primary school

b. Probability of no violent crime during the year