A pharmaceutical company wishes to test a new drug with the expectation of lowering cholesterol levels. Ten subjects are randomly selected and pretested. The results are listed below. The subjects were placed on the drug for a period of 6 months, after which their cholesterol levels were tested again. The results are listed below. (All units are milligrams per deciliter.) Test the company's claim that the drug lowers cholesterol levels. Use α = 0.01. Assume that the distribution is normally distributed. Subject 1 2 3 4 5 6 7 8 9 10 Before 195 225 202 195 175 250 235 268 190 240 After 180 220 210 175 170 250 205 250 190 225 Construct a 99% confidence interval before and after taking the new drug.
Added by Kayla F.
Step 1
Given data for before: Mean (X̄1) = 217.50 Standard Deviation (S1) = 30.35 Sample Size (n1) = 10 Given data for after: Mean (X̄2) = 207.50 Standard Deviation (S2) = 29.08 Sample Size (n2) = 10 Show more…
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'A pharmaceutical company has developed a new drug which they believe will reduce cholesterol levels. 21 patients were randomly assigned to the treatment group (receive new drug) Another 23 patients were assigned to the control group (received existing drug). The "before" cholesterol value for each patient was recorded; then the "after" cholesterol value, and finally the total cholesterol reduction for each patient was recorded. Here is the data: x(bar) Treatment group (new drug) 21 22.45 7.99 Control group (old drug) 23 18.52 7.15 Calculate a 90% confidence interval for the difference in reduction of cholesterol between these two drugs Use Option 1 (technology) for degrees of freedom and round to three decimal places. The lower bound of confidence interval is:'
Lien L.
A pharmaceutical company is testing a new drug that is supposed to lower cholesterol levels. Ten volunteers participate in a 3 month study that compares their cholesterol level before and after the 3 month treatment. The results are below. Units of measure are mg/dL. Initial Level. 210 200 215 194 206 221 203 189 208 211 Level after 3 months 201 195 208 197 200 203 190 188 210 210 Construct and interpret a 95% confidence interval for the true mean decrease in cholesterol levels for people who take the drug treatment for 3 months. For credit, your work must include a filled out formula for your confidence interval. If it helps, you may follow the steps outlined in the previous problem.
Keondre P.
Daily Cholesterol Intake The American Heart Association recommends a daily cholesterol intake of less than $300 \mathrm{mg}$. Here are the cholesterol amounts in a random sample of single servings of grilled meats. Estimate the standard deviation in cholesterol with $95 \%$ confidence. Assume the variable is normally distributed. $$ \begin{array}{ccccc}{90} & {200} & {80} & {105} & {95} \\ {85} & {70} & {105} & {115} & {110} \\ {100} & {225} & {125} & {130} & {145}\end{array} $$
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