Question: A quality-control technician with a bath soap manufacturer periodically draws samples of size 50 from the assembly line and examines each bar of soap for defects. The following table shows the number of defective bars of soap in each of the last 25 samples drawn. Determine whether or not the process appears to be in control.

Sample Number of Sample Number of Number defective bars number defective bars 1 2 13 4
2 2 14 4
3 0 15 4
4 3 16 0
5 2 17 2
6 10 18 0
7 4 19 10
8 10 20 4
9 0 21 2
10 4 22 1
11 14 23 0
12 10 24 3
25 5