Expiration dates that establish the shelf lives of pharmaceutical products are determined from stability data in drug formulatio
n studies. In order to measure the rate of decomposition of a particular drug, it is stored under various conditions of temperature, humidity, light intensity, etc., and assayed for intact drug potency at FDA-recommended time intervals of every three months during the first year. In this example, the assay Y (mg) of a certain 500 mg tablet formulation is determined at time X (months) under ambient storage conditions.
X 0 3 6 9 12
Y 500 490 470 430 350
(a) Graph these data points (xi , yi) in a scatterplot, and calculate the sample correlation coefficient r=Sxy/Sx.Sy. Classify the correlation as positive or negative, and as weak, moderate, or strong.
(b) Determine the equation of the least-squares regression line for these data points, and include a 95% confidence interval for the slope β1.
(c) Sketch a graph of this line on the same set of axes as part (a); also calculate and plot the fitted response values y, and the residuals ei= yi - ŷi, on this graph.
(d) Complete an ANOVA table for this linear regression, including the F-ratio and corresponding p-value.
X 0 3 6 9 12
Y 500 490 470 430 350
(a) Graph these data points (xi , yi) in a scatterplot, and calculate the sample correlation coefficient r=Sxy/Sx.Sy. Classify the correlation as positive or negative, and as weak, moderate, or strong.
(b) Determine the equation of the least-squares regression line for these data points, and include a 95% confidence interval for the slope β1.
(c) Sketch a graph of this line on the same set of axes as part (a); also calculate and plot the fitted response values y, and the residuals ei= yi - ŷi, on this graph.
(d) Complete an ANOVA table for this linear regression, including the F-ratio and corresponding p-value.
1 answer:
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Answer:
i. The ratio of the areas of the two triangles is 5:8.
ii. The area of the larger triangle is 24 in².
Step-by-step explanation:
Let the area of the smaller triangle be represented by , and that of the larger triangle by
.
Area of a triangle = x b x h
Where; b is its base and h the height.
Thus,
a. The ratio of the area of the two triangles is:
Area of smaller triangle = x b x h
= x 5 x h
= h
Area of the lager triangle = x b x h
= x 8 x h
= 4h
So that;
Ratio =
=
The ratio of the areas of the two triangles is 5:8.
b. If the area of the smaller triangle is 15 in², then the area of the larger triangle can be determined as;
=
=
5 = 15 x 8
= 120
=
= 24
The area of the larger triangle is 24 in².