Q. 97 - The Practice of Statistics for AP

Question

Phosphate levels The level of various substances in the blood influences our health. Here are measurements of the level of phosphate in the blood of a patient, in milligrams of phosphate per deciliter of blood, made on 6 consecutive visits to a clinic: 5.6, 5.2, 4.6, 4.9, 5.7, 6.4. A graph of only 6 observations gives little information, so we proceed to compute the mean and standard deviation. (a) Find the standard deviation from its definition. That is, find the deviations of each observation from the mean, square the deviations, then obtain the variance and the standard deviation. (b) Interpret the value of sx you obtained in (a) 

Step-by-Step Solution

Answer

a. $\overline{x}=5.4$mg/dI and $s_x=0.6419$ mg/dI

 b. The phosphate level varies  at 0.6418 mg/dI 

Step 1: Identify key features

Determine intercepts, asymptotes, critical points, and end behavior.

Step 2: Plot the graph

Plot key features and connect them to form the complete graph.