In: Math
In the following problem, check that it is appropriate to use
the normal approximation to the binomial. Then use the normal
distribution to estimate the requested probabilities.
What are the chances that a person who is murdered actually knew
the murderer? The answer to this question explains why a lot of
police detective work begins with relatives and friends of the
victim! About 68% of people who are murdered
actually knew the person who committed the murder.† Suppose that a
detective file in New Orleans has 65 current
unsolved murders. Find the following probabilities. (Round your
answers to four decimal places.)
(a) at least 35 of the victims knew their murderers
(b) at most 48 of the victims knew their murderers
(c) fewer than 30 victims did not know their murderers
(d) more than 20 victims did not know their murderers