The answer to me is B........
Answer:
The null hypothesis ![H_o : \mu = 3.2 \ mg/dl](https://tex.z-dn.net/?f=H_o%20%3A%20%20%5Cmu%20%3D%203.2%20%5C%20mg%2Fdl)
The alternative hypothesis ![H_a : \mu > 3.2 \ mg/dl](https://tex.z-dn.net/?f=H_a%20%3A%20%20%5Cmu%20%3E%203.2%20%5C%20mg%2Fdl)
Step-by-step explanation:
From the question we are told that
The mean is ![\mu = 3.2 \ mg/dl](https://tex.z-dn.net/?f=%5Cmu%20%3D%203.2%20%5C%20%20mg%2Fdl)
The standard deviation is ![\sigma = 1.5 mg/dl](https://tex.z-dn.net/?f=%5Csigma%20%3D%20%201.5%20mg%2Fdl)
The sample size is n = 25
The sample mean is ![\= x = 3.75 \ mg /dl](https://tex.z-dn.net/?f=%5C%3D%20x%20%3D%203.75%20%5C%20%20mg%20%2Fdl)
Generally
The null hypothesis is : That the mean of the Arsenic blood concentrations in healthy individuals is ![\mu = 3.2 \ mg/dl](https://tex.z-dn.net/?f=%5Cmu%20%3D%203.2%20%5C%20%20mg%2Fdl)
i.e
The null hypothesis ![H_o : \mu = 3.2 \ mg/dl](https://tex.z-dn.net/?f=H_o%20%3A%20%20%5Cmu%20%3D%203.2%20%5C%20mg%2Fdl)
The alternative hypothesis is : That the mean of the Arsenic blood concentrations in healthy individuals is greater than ![\mu = 3.2 \ mg/dl](https://tex.z-dn.net/?f=%5Cmu%20%3D%203.2%20%5C%20%20mg%2Fdl)
The alternative hypothesis ![H_a : \mu > 3.2 \ mg/dl](https://tex.z-dn.net/?f=H_a%20%3A%20%20%5Cmu%20%3E%203.2%20%5C%20mg%2Fdl)
Answer:
![x=9](https://tex.z-dn.net/?f=x%3D9)
Step-by-step explanation:
ABC is the sum of the angles CBD and ABD. So:
![\angle ABC=\angle CBD+\angle ABD](https://tex.z-dn.net/?f=%5Cangle%20ABC%3D%5Cangle%20CBD%2B%5Cangle%20ABD)
Substitute them for their equations:
![(-7x+241)=(-4x+123)+(154-7x)](https://tex.z-dn.net/?f=%28-7x%2B241%29%3D%28-4x%2B123%29%2B%28154-7x%29)
Solve for x. Combine like terms on the right:
![-7x+241=-11x+277](https://tex.z-dn.net/?f=-7x%2B241%3D-11x%2B277)
Add 11x to both sides:
![4x+241=277](https://tex.z-dn.net/?f=4x%2B241%3D277)
Subtract 241 from both sides:
![4x=36](https://tex.z-dn.net/?f=4x%3D36)
Divide both sides by 4:
![x=9](https://tex.z-dn.net/?f=x%3D9)
The value of x is 9.
And we're done!