The management of the Diner Delight franchised restaurant chain is in the process of establishing quality control charts for the time that its service people give to each customer. Management thinks the length of time that each customer is given should remain within certain limits to enhance service quality.

A sample of six service people was selected, and the customer service they provided was observed four times. The activities that the service people were performing were identified, and the time to service one customer was recorded as noted below:

Service Person	Sample 1	Sample 2	Sample 3	Sample 4
1	200	150	175	90
2	120	85	105	75
3	83	93	130	150
4	68	150	145	175
5	110	90	75	105
6	115	65	115	125

Determine the upper and lower control limits for an X-bar and an R-chart with a sample size of 6.

Olivia joined Diners Delight after the control chart was established. The following sample of her customer service times in seconds was recorded: 180, 125, 110, 98, 156, and 190. How is Olivia doing?