The level of various substances in the blood of kidney dialysispatients is of concern because kidney failure and dialysis can leadto nutritional problems. A researcher performed blood tests onseveral dialysis patients on 6 consecutive clinic visits. Onevariable measured was the level of phosphate in the blood.Phosphate levels for an individual tend to vary normally over time.The data on one patient, in milligrams of phosphate per deciliter(mg/dl) of blood, are given below.
(a) Calculate the sample mean x and its standarderror.
x =Â Â
Sx =
(b) Use the t procedures to find the margin of error for a90% confidence interval for this patient's mean phosphatelevel.
margin of error =Â Â
(c) Use the t procedures to give a 90% confidence intervalfor this patient's mean phosphate level.
90% CI = (______ , _______ )
