Answer:
B. Hannah is likely to be incorrect because 9 is not contained in the interval.
Step-by-step explanation:
She construct a 99% confidence interval for the difference between means and gets the interval (0.4, 8.0).
This means that there is 99% confidence that the true difference between means is within this interval.
The left 1% corresponds to the tails of the distribution: there is 0.5% probability that the difference between means is below 0.4 and 0.5% probability that the difference between means is above 8.0.
As she claims that 9 hours is the true difference, we can say that there is less than 0.5% that she is correct. In others words, is likely to be incorrect.
The expression should be (2/h)x(k+8).
Answer: C
Step-by-step explanation:
Given 2 similar solids whose
ratio of sides = a : b, then
ratio of areas = a^2 : b^2 and
ratio of volumes = a^3 : b^3
Here the area ratio = 169 : 81, thus
side ratio = sqrt{169} : sqrt{81} = 13 : 9
Hence the volume ratio = 13^3 : 9^3
Using proportion then
frac{13^3}{9^3} = frac{124.92}{x} → C
