Lie detector tests are notoriously flawed Assume that a part
     Lie detector tests are notoriously flawed.  Assume that a particular test gives false positives with probability 0.2 and false negatives with probability 0.1.  In a large workforce assume that 15 percentage of applicants lie.  What is the probability that if the lie detector test says a random applicant lies that the applicant really is lying. 
  
  Solution

