Four inspectors stamp dates on film. Their proportions of all dates stamped (S) and their rates of errors for each for 200 they personally stamped are shown below:
John 15% 3
Tom 55% 2
Jeff 11% 4
Pat 19% 1
A) what is the probability that a given stamp will be dated incorrectly?
B) If it is dated incorrectly, what is the probability that John stamped it?
Answers: I just need to know how to get to them
(A) Probability that a given stamp will be dated incorrectly
= (0.15 * 3/200) ...
The Solution provides the required probabilities neatly worked out.