A large bakery regularly takes samples of bread in order to ensure that its product meets quality specifications. Each loaf that is sampled is first weighed and weight records of 765 ‘standard’ sliced loaves have accumulated over the last few months. The Quality Control Manager would like these records analyzed and has aggregated the data into the following frequency table.
Weight Range Number of Loaves
780g below to 790g 34
790g below to 795g 80
795g below to 800g 111
800g below to 805g 162
805g below to 810g 161
810g below to 815g 120
815g below to 820g 70
820g below to 830g 27
(a) Analyze these figures and write a report to the Quality Control Manager. Your analysis should include measures of location and spread of the data.
(b) Construct a 99% confidence interval for the mean number of loaves over the last few months.