Answer:
The degrees of freedom are given by:
![df = n_A +n_B -2 = 18 +15-2= 31](https://tex.z-dn.net/?f=%20df%20%3D%20n_A%20%2Bn_B%20-2%20%3D%2018%20%2B15-2%3D%2031)
And the 90% confidence interval for this case is:
![-1.90 \leq \mu_A -\mu_B \leq 0.13](https://tex.z-dn.net/?f=%20-1.90%20%5Cleq%20%5Cmu_A%20-%5Cmu_B%20%5Cleq%200.13)
And for this case since the confidence interval contains the value 0 we can conclude that:
A. We are 90% confident that, on average, there is no difference in operating hours between toothbrushes from Company A compared to those from Company B.
Step-by-step explanation:
We know the following info given:
sample mean for A
sample deviation for A
sample size from A
sample mean for B
sample deviation for B
sample size from B
The degrees of freedom are given by:
![df = n_A +n_B -2 = 18 +15-2= 31](https://tex.z-dn.net/?f=%20df%20%3D%20n_A%20%2Bn_B%20-2%20%3D%2018%20%2B15-2%3D%2031)
And the 90% confidence interval for this case is:
![-1.90 \leq \mu_A -\mu_B \leq 0.13](https://tex.z-dn.net/?f=%20-1.90%20%5Cleq%20%5Cmu_A%20-%5Cmu_B%20%5Cleq%200.13)
And for this case since the confidence interval contains the value 0 we can conclude that:
A. We are 90% confident that, on average, there is no difference in operating hours between toothbrushes from Company A compared to those from Company B.
Answer:
9 feet
Step-by-step explanation:
The given is 30-60-90 special triangle with the side lengths as follows
x-x√(3- and 2x
The side length that sees 90 degrees (hypotenuse) is 18 which means x = 9
then the side length that sees 30 degrees is 9 as well
The volume of a cylinder:
![V=\pi r^2 h](https://tex.z-dn.net/?f=V%3D%5Cpi%20r%5E2%20h)
r - radius, h - height
![r=8 \ in \\ h=15 \ in \\ \pi \approx 3.14 \\ \\ V=3.14 \times 8^2 \times 15=3.14 \times 64 \times 15=3014.4 \ [in^3]](https://tex.z-dn.net/?f=r%3D8%20%5C%20in%20%5C%5C%0Ah%3D15%20%5C%20in%20%5C%5C%0A%5Cpi%20%5Capprox%203.14%20%5C%5C%20%5C%5C%0AV%3D3.14%20%5Ctimes%208%5E2%20%5Ctimes%2015%3D3.14%20%5Ctimes%2064%20%5Ctimes%2015%3D3014.4%20%5C%20%5Bin%5E3%5D)
The answer is
C.
Can you show the graph? i can help explain what to do after.