Answer:
I'm assuming you meant
, if so the answer is
Step-by-step explanation:
hope this helps :)
To solve an addition problem, you simply add one number to the other. For example,
If I want to add 4 to 5, I would write the equation 4 + 5 = 9.
To solve a subtraction problem, you simply take a number away from another. For example,
If I want to take 5 away from 9, I would write the equation 9 - 5 = 4.
Hope I helped! :)
Answer:
2 = x- coordinate
3 = y coordinate
Step-by-step explanation:
REMEMBER: In an ordered pair, the x-coordinate always comes first.
Answer:
![(a)\ \bar x_1 - \bar x_2 = 2.0](https://tex.z-dn.net/?f=%28a%29%5C%20%5Cbar%20x_1%20-%20%5Cbar%20x_2%20%3D%202.0)
![(b)\ CI =(1.0542,2.9458)](https://tex.z-dn.net/?f=%28b%29%5C%20CI%20%3D%281.0542%2C2.9458%29)
![(c)\ CI = (0.8730,2.1270)](https://tex.z-dn.net/?f=%28c%29%5C%20CI%20%3D%20%280.8730%2C2.1270%29)
Step-by-step explanation:
Given
![\sigma_2 = 3](https://tex.z-dn.net/?f=%5Csigma_2%20%3D%203)
Solving (a): Point estimate of difference of mean
This is calculated as: ![\bar x_1 - \bar x_2](https://tex.z-dn.net/?f=%5Cbar%20x_1%20-%20%5Cbar%20x_2)
![\bar x_1 - \bar x_2 = 13.6 - 11.6](https://tex.z-dn.net/?f=%5Cbar%20x_1%20-%20%5Cbar%20x_2%20%3D%2013.6%20-%2011.6)
![\bar x_1 - \bar x_2 = 2.0](https://tex.z-dn.net/?f=%5Cbar%20x_1%20-%20%5Cbar%20x_2%20%3D%202.0)
Solving (b): 90% confidence interval
We have:
![c = 90\%](https://tex.z-dn.net/?f=c%20%3D%2090%5C%25)
![c = 0.90](https://tex.z-dn.net/?f=c%20%3D%200.90)
Confidence level is: ![1 - \alpha](https://tex.z-dn.net/?f=1%20-%20%5Calpha)
![1 - \alpha = c](https://tex.z-dn.net/?f=1%20-%20%5Calpha%20%3D%20c)
![1 - \alpha = 0.90](https://tex.z-dn.net/?f=1%20-%20%5Calpha%20%3D%200.90)
![\alpha = 0.10](https://tex.z-dn.net/?f=%5Calpha%20%3D%200.10)
Calculate ![z_{\alpha/2}](https://tex.z-dn.net/?f=z_%7B%5Calpha%2F2%7D)
![z_{\alpha/2} = z_{0.10/2}](https://tex.z-dn.net/?f=z_%7B%5Calpha%2F2%7D%20%3D%20z_%7B0.10%2F2%7D)
![z_{\alpha/2} = z_{0.05}](https://tex.z-dn.net/?f=z_%7B%5Calpha%2F2%7D%20%3D%20z_%7B0.05%7D)
The z score is:
![z_{\alpha/2} = z_{0.05} =1.645](https://tex.z-dn.net/?f=z_%7B%5Calpha%2F2%7D%20%3D%20z_%7B0.05%7D%20%3D1.645)
The endpoints of the confidence level is:
![(\bar x_1 - \bar x_2) \± z_{\alpha/2} * \sqrt{\frac{\sigma_1^2}{n_1}+\frac{\sigma_2^2}{n_2}}](https://tex.z-dn.net/?f=%28%5Cbar%20x_1%20-%20%5Cbar%20x_2%29%20%5C%C2%B1%20z_%7B%5Calpha%2F2%7D%20%2A%20%5Csqrt%7B%5Cfrac%7B%5Csigma_1%5E2%7D%7Bn_1%7D%2B%5Cfrac%7B%5Csigma_2%5E2%7D%7Bn_2%7D%7D)
![2.0 \± 1.645 * \sqrt{\frac{2.1^2}{60}+\frac{3^2}{35}}](https://tex.z-dn.net/?f=2.0%20%5C%C2%B1%201.645%20%2A%20%5Csqrt%7B%5Cfrac%7B2.1%5E2%7D%7B60%7D%2B%5Cfrac%7B3%5E2%7D%7B35%7D%7D)
![2.0 \± 1.645 * \sqrt{\frac{4.41}{60}+\frac{9}{35}}](https://tex.z-dn.net/?f=2.0%20%5C%C2%B1%201.645%20%2A%20%5Csqrt%7B%5Cfrac%7B4.41%7D%7B60%7D%2B%5Cfrac%7B9%7D%7B35%7D%7D)
![2.0 \± 1.645 * \sqrt{0.0735+0.2571}](https://tex.z-dn.net/?f=2.0%20%5C%C2%B1%201.645%20%2A%20%5Csqrt%7B0.0735%2B0.2571%7D)
![2.0 \± 1.645 * \sqrt{0.3306}](https://tex.z-dn.net/?f=2.0%20%5C%C2%B1%201.645%20%2A%20%5Csqrt%7B0.3306%7D)
![2.0 \± 0.9458](https://tex.z-dn.net/?f=2.0%20%5C%C2%B1%200.9458)
Split
![(2.0 - 0.9458) \to (2.0 + 0.9458)](https://tex.z-dn.net/?f=%282.0%20-%200.9458%29%20%5Cto%20%282.0%20%2B%200.9458%29)
![(1.0542) \to (2.9458)](https://tex.z-dn.net/?f=%281.0542%29%20%5Cto%20%282.9458%29)
Hence, the 90% confidence interval is:
![CI =(1.0542,2.9458)](https://tex.z-dn.net/?f=CI%20%3D%281.0542%2C2.9458%29)
Solving (c): 95% confidence interval
We have:
![c = 95\%](https://tex.z-dn.net/?f=c%20%3D%2095%5C%25)
![c = 0.95](https://tex.z-dn.net/?f=c%20%3D%200.95)
Confidence level is: ![1 - \alpha](https://tex.z-dn.net/?f=1%20-%20%5Calpha)
![1 - \alpha = c](https://tex.z-dn.net/?f=1%20-%20%5Calpha%20%3D%20c)
![1 - \alpha = 0.95](https://tex.z-dn.net/?f=1%20-%20%5Calpha%20%3D%200.95)
![\alpha = 0.05](https://tex.z-dn.net/?f=%5Calpha%20%3D%200.05)
Calculate ![z_{\alpha/2}](https://tex.z-dn.net/?f=z_%7B%5Calpha%2F2%7D)
![z_{\alpha/2} = z_{0.05/2}](https://tex.z-dn.net/?f=z_%7B%5Calpha%2F2%7D%20%3D%20z_%7B0.05%2F2%7D)
![z_{\alpha/2} = z_{0.025}](https://tex.z-dn.net/?f=z_%7B%5Calpha%2F2%7D%20%3D%20z_%7B0.025%7D)
The z score is:
![z_{\alpha/2} = z_{0.025} =1.96](https://tex.z-dn.net/?f=z_%7B%5Calpha%2F2%7D%20%3D%20z_%7B0.025%7D%20%3D1.96)
The endpoints of the confidence level is:
![(\bar x_1 - \bar x_2) \± z_{\alpha/2} * \sqrt{\frac{\sigma_1^2}{n_1}+\frac{\sigma_2^2}{n_2}}](https://tex.z-dn.net/?f=%28%5Cbar%20x_1%20-%20%5Cbar%20x_2%29%20%5C%C2%B1%20z_%7B%5Calpha%2F2%7D%20%2A%20%5Csqrt%7B%5Cfrac%7B%5Csigma_1%5E2%7D%7Bn_1%7D%2B%5Cfrac%7B%5Csigma_2%5E2%7D%7Bn_2%7D%7D)
![2.0 \± 1.96 * \sqrt{\frac{2.1^2}{60}+\frac{3^2}{35}}](https://tex.z-dn.net/?f=2.0%20%5C%C2%B1%201.96%20%2A%20%5Csqrt%7B%5Cfrac%7B2.1%5E2%7D%7B60%7D%2B%5Cfrac%7B3%5E2%7D%7B35%7D%7D)
![2.0 \± 1.96* \sqrt{\frac{4.41}{60}+\frac{9}{35}}](https://tex.z-dn.net/?f=2.0%20%5C%C2%B1%201.96%2A%20%5Csqrt%7B%5Cfrac%7B4.41%7D%7B60%7D%2B%5Cfrac%7B9%7D%7B35%7D%7D)
![2.0 \± 1.96 * \sqrt{0.0735+0.2571}](https://tex.z-dn.net/?f=2.0%20%5C%C2%B1%201.96%20%2A%20%5Csqrt%7B0.0735%2B0.2571%7D)
![2.0 \± 1.96* \sqrt{0.3306}](https://tex.z-dn.net/?f=2.0%20%5C%C2%B1%201.96%2A%20%5Csqrt%7B0.3306%7D)
![2.0 \± 1.1270](https://tex.z-dn.net/?f=2.0%20%5C%C2%B1%201.1270)
Split
![(2.0 - 1.1270) \to (2.0 + 1.1270)](https://tex.z-dn.net/?f=%282.0%20-%201.1270%29%20%5Cto%20%282.0%20%2B%201.1270%29)
![(0.8730) \to (2.1270)](https://tex.z-dn.net/?f=%280.8730%29%20%5Cto%20%282.1270%29)
Hence, the 95% confidence interval is:
![CI = (0.8730,2.1270)](https://tex.z-dn.net/?f=CI%20%3D%20%280.8730%2C2.1270%29)