Question

A sample of blood pressure measurements is taken for a group of adults, and those values (mm Hg) are listed below. The values are matched so that 10 subjects each have a systolic and diastolic measurement. Find the coefficient of variation for each of the two samples; then compare the variation.

Systolic 120 128 156 98 154 122 118 136 128 120 -
Diastolic 79 76 75 51 92 87 59 64 72 81

The coefficient of variation for the systolic measurements is ________​%. ​(Type an integer or decimal rounded to one decimal place as​ needed.)
The coefficient of variation for the diastolic measurements is ________​%. ​(Type an integer or decimal rounded to one decimal place as​ needed.)

Answer 1

Answer:

The coefficient of variation for the systolic measurements is 12.8 %

The coefficient of variation for the diastolic measurements is 16.3 %

Therefore, we can conclude that the systolic measurements are less dispersed as compared to diastolic measurements.

Step-by-step explanation:

The coefficient of variation is the ratio of standard deviation of the data to the mean of the data. It shows the dispersion in the data set.

Coefficient of variation for the systolic measurements:

Mean = μ = (120 + 128 + 156 + 98 + 154 + 122 + 118 + 136 + 128 + 120)/10

Mean = μ = 1280/10

Mean = μ = 128

Standard deviation = σ = $\sqrt{\frac{1}{N}\sum_ (x-\mu)^{2} }$

Using excel the standard deviation is found to be

Standard deviation = σ = 16.4

Coefficient of variation = σ/μ

Coefficient of variation = 16.4/128

Coefficient of variation = 0.128

Coefficient of variation = 12.8%

Coefficient of variation for the Diastolic measurements:

Mean = μ = (79 + 76 + 75 + 51 + 92 + 87 + 59 + 64 + 72 + 81)/10

Mean = μ = 736/10

Mean = μ = 73.6

Standard deviation = σ = $\sqrt{\frac{1}{N}\sum_ (x-\mu)^{2} }$

Using excel the standard deviation is found to be

Standard deviation = σ = 12

Coefficient of variation = σ/μ

Coefficient of variation = 12/73.6

Coefficient of variation = 0.163

Coefficient of variation = 16.3%

Conclusion:

We can conclude that the systolic measurements (12.8%) are less dispersed as compared to diastolic measurements (16.3%).