Question

low - density lipoprotein (ldl) is an important part of blood cholesterol test. ldl higher than 130mg/dl is a risk factor of developing cardiovascular disease. to prevent cardiovascular disease, a health center had a free blood cholesterol test for all the people older than 65 in the community. a total of eight people attended the blood screening and their blood test results are listed below: ldl(mg/dl): 130,143,114,110,123,110,134,124. after the blood test, the nurse wants to know the mean ldl score: a. 125 b. 120 c. 123.5 d. 123

Explanation:

Step1: Recall mean formula

The mean $\bar{x}=\frac{\sum_{i = 1}^{n}x_{i}}{n}$, where $x_{i}$ are the data - points and $n$ is the number of data - points. Here $n = 8$, and $x_{1}=130,x_{2}=143,x_{3}=114,x_{4}=110,x_{5}=123,x_{6}=110,x_{7}=134,x_{8}=124$.

Step2: Calculate the sum of data - points

$\sum_{i = 1}^{8}x_{i}=130 + 143+114+110+123+110+134+124=988$.

Step3: Calculate the mean

$\bar{x}=\frac{988}{8}=123.5$.

Answer:

C. 123.5