Six different second-year medical students at bellevue hospital measured the blood pressure of the same person. the systolic readings (in mmhg) 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? 127 150 121 120 140 128

1. Range =30

2. Variance =137.6

3. Standard deviation=11.7303

Step-by-step explanation:

This question requires you to find the range, variance and standard deviation of sample data set.

Given the data as; 127 150 121 120 140 128

Arrange the data in ascending order;

sample set S={120, 121, 127, 128, 140, 150}

number of elements, n=6

1. Range = Maximum (S) - Minimum (S) = 150- 120 = 30

⇒Find the mean of the data set

2. Variance is the measure of how far a set of data is spread out.Standard deviation is the square-root of variance.To find variance you need to follow the steps below;

Finding the deviations from the mean and their squares

Deviations             Squares of deviations

120-131= -11               -11²=   121

121-131= -10                -10² =100

127-131= -4                  -4² = 16

128-131= -3                   -3= 9

140-131= 9                    9²=  81

150-131= 19                19²=  361

Finding the sum of the squares of the deviations from the mean

Finding the variance

Variance, S²=(sum of squares of deviations from mean)/ n-1

Finding standard deviation

Standard deviation , s , is the square-root of the variance 

i am unable to solve this problem

step-by-step explanation: