In: Statistics and Probability
A soft-drink bottling company maintains records of the number of unacceptable bottles obtained from its two filling and capping machines. A trial inspection of a production run of 1000 bottles showed that 430 came from Machine I and 570 from Machine II. Ten bottles from Machine I and 25 from Machine II were nonconforming.
(a) Use the above information to estimate the probabilities in the contingency table:
| 
 Conforming  | 
 Nonconforming  | 
 TOTAL  | 
|
| 
 Machine I  | 
|||
| 
 Machine II  | 
|||
| 
 TOTAL  | 
(b) What proportion of the total output is nonconforming?
(c) If a randomly-chosen bottle is found to be nonconforming, what is the probability that it was produced on Machine II?
(d) Which machine seems to be better? Calculate relevant probabilities and discuss.