Academic Integrity: tutoring, explanations, and feedback — we don’t complete graded work or submit on a student’s behalf.

Six different second-year medical students at Bellevue Hospital measured the blo

ID: 3263806 • Letter: S

Question

Six different second-year medical students at Bellevue Hospital measured the blood pressure of the same person. The systolic readings (in mm Hg) are listed below. Find the range, variance, and standard deviation for the given sample data. If the subject's blood pressure remains constant and the medical students correctly apply the same measurement technique, what should be the value of the standard deviation? 127 132 142 141 147 130 Range = 20 mmHg Sample variance = mmHg^2 (Round to the nearest tenth as needed.)

Explanation / Answer

Let the given variable is x

x

127

132

142

141

147

130

Sample variance = S ( x – x bar )^2 / (n-1)

x

127

132

142

141

147

130

Total =

819

x bar = S x / n

          = 819 / 6

          = 136.5

x

(x - x bar)

(x - x bar)^2

127

-9.5

90.25

132

-4.5

20.25

142

5.5

30.25

141

4.5

20.25

147

10.5

110.25

130

-6.5

42.25

Total =

313.5

Sample variance = S ( x – x bar )^2 / (n-1)

                               = 313.5 / (6-1)

                                = 313.5/5

                          = 62.7

Answer: 62.7

x

127

132

142

141

147

130