Instruction 15-4
One Criterion Used to Evaluate Employees in the Assembly

Instruction 15-4
One criterion used to evaluate employees in the assembly section of a large factory is the number of defective pieces per 1,000 parts produced.The quality control department wants to find out whether there is a relationship between years of experience and defect rate.Since the job is repetitious,after the initial training period any improvement due to a learning effect might be offset by a loss of motivation.A defect rate is calculated for each worker in a yearly evaluation.The results for 100 workers are given in the table below.
Years Since Training Period
$$\begin{array} { | r | l | c | c | c | } \hline & & < \mathbf { 1 } \text { Year } & \text { 1 - 4 Years } & \text { 5 - 9 Years } \\\hline & \text { High } & 6 & 9 & 9 \\\hline \text { Defect Rate: } & { \text { Average } } & 9 & 19 & 23 \\\hline & \text { Low } & 7 & 8 & 10 \\\hline\end{array}$$
-Referring to Instruction 15-4,what is the expected number of employees with less than 1 year of training time and a high defect rate?

A) 4.17
B) 4.60
C) 9.17
D) 5.28