Question

The inspector in charge of a criminal investigation is 60 percent certain of the guilt of a certain suspect. a new piece of evidence proving that the criminal was left-handed has just been discovered. whereas the inspector knows that 18 percent of the population is left-handed, she is waiting to find out whether the suspect is left-handed.

(a) what is the probability that the suspect is left-handed?
(b) if the suspect turns out to be left-handed, what is the probability that the suspect is guilty?

Answer 1

The probability the suspect is left-handed is 18 percent, and if the suspect is indeed left-handed, the probability that they are guilty remains at the inspector's initial confidence of 60 percent, unless further evidence is provided.

Step-by-step explanation:

The question deals with applying basic rules of probability to a criminal investigation context.

Part (a): Probability of Suspect Being Left-Handed

The probability that the suspect is left-handed is the same as the general population, assuming no other information is provided that would influence this. Therefore, the probability is 18 percent.

Part (b): Probability of Guilt if the Suspect is Left-Handed

If the suspect turns out to be left-handed, this does not necessarily change the probability of guilt established by the inspector’s initial belief. Without additional information linking left-handedness to the specific crime or adjusting the initial probability based on the new evidence, the inspector's confidence in the suspect's guilt remains at 60 percent.