Question

As part of a research program for a new cholesterol drug, a pharmaceutical company would like to investigate the relationship between the ages and LDL (low-density lipoprotein) cholesterol of men. The following data set shows the ages and LDL cholesterol levels of seven randomly selected men. Construct a 95% confidence interval to estimate the average LDL cholesterol level of a 29-year-old man. Click the icon to view the data table. Determine the upper and lower limits of the confidence interval Data Table UCL- LCLEO (Round to one decimal place as needed.) Corr Age Cholesterol 22 140 36 26 175 160 32 195 4231 156 144 40 207 Print Done

Answer 1

Solution dx x-A x -168 140 -28 784 175 7 49 160 -8 64 195 27 729 156 -12 144 144 -24 576 207 39 1521 Σx-177 Σω)-1 Σω-3367 Σχ Mean 140 175 160 195 156 144 + 207 7 1177 7 168.1429 (Σά). Σα. Sample Standard deviation $ = 1 (1)2 3867 7 6 3867 - 0.1429 6 3866.8571 644.4762 - 25.3865

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Solution: Given That- CI 95% X 168.14 df n-1 df 6 7 n = 25.3865 S 95% Confidence Level't' is, At a 1 95% a 1 0.95 a 0.05 a/2 0.025 t a/2, df 2.4469 95% Confidence Interval for Mean is, At n

CI for Mean using t CI for 95% n 7 mean 168.14 t-value of 95% CI and df 6 std. dev. SE std.dev./sqrt(n) ME t*SE Lower Limit Mean ME 2.45 25.3865 9.59520 23.47860 144.66140 Upper Limit Mean ME 95% CI 191.61860 (144.6614,191.6186)

AT 95 % CI for Mean is,

UCL = 191.6

LCL = 144.7

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