Answer:
There is a significant difference between the two proportions.
Step-by-step explanation:
The (1 - <em>α</em>)% confidence interval for difference between population proportions is:
![CI=(\hat p_{1}-\hat p_{2})\pm z_{\alpha/2}\times\sqrt{\frac{\hat p_{1}(1-\hat p_{1})}{n_{1}}+\frac{\hat p_{2}(1-\hat p_{2})}{n_{2}}}](https://tex.z-dn.net/?f=CI%3D%28%5Chat%20p_%7B1%7D-%5Chat%20p_%7B2%7D%29%5Cpm%20z_%7B%5Calpha%2F2%7D%5Ctimes%5Csqrt%7B%5Cfrac%7B%5Chat%20p_%7B1%7D%281-%5Chat%20p_%7B1%7D%29%7D%7Bn_%7B1%7D%7D%2B%5Cfrac%7B%5Chat%20p_%7B2%7D%281-%5Chat%20p_%7B2%7D%29%7D%7Bn_%7B2%7D%7D%7D)
Compute the sample proportions as follows:
![\hat p_{1}=\frac{80}{250}=0.32\\\\\hat p_{2}=\frac{40}{175}=0.23](https://tex.z-dn.net/?f=%5Chat%20p_%7B1%7D%3D%5Cfrac%7B80%7D%7B250%7D%3D0.32%5C%5C%5C%5C%5Chat%20p_%7B2%7D%3D%5Cfrac%7B40%7D%7B175%7D%3D0.23)
The critical value of <em>z</em> for 90% confidence interval is:
![z_{0.10/2}=z_{0.05}=1.645](https://tex.z-dn.net/?f=z_%7B0.10%2F2%7D%3Dz_%7B0.05%7D%3D1.645)
Compute a 90% confidence interval for the difference between the proportions of women in these two fields of engineering as follows:
![CI=(\hat p_{1}-\hat p_{2})\pm z_{\alpha/2}\times\sqrt{\frac{\hat p_{1}(1-\hat p_{1})}{n_{1}}+\frac{\hat p_{2}(1-\hat p_{2})}{n_{2}}}](https://tex.z-dn.net/?f=CI%3D%28%5Chat%20p_%7B1%7D-%5Chat%20p_%7B2%7D%29%5Cpm%20z_%7B%5Calpha%2F2%7D%5Ctimes%5Csqrt%7B%5Cfrac%7B%5Chat%20p_%7B1%7D%281-%5Chat%20p_%7B1%7D%29%7D%7Bn_%7B1%7D%7D%2B%5Cfrac%7B%5Chat%20p_%7B2%7D%281-%5Chat%20p_%7B2%7D%29%7D%7Bn_%7B2%7D%7D%7D)
![=(0.32-0.23)\pm 1.645\times\sqrt{\frac{0.32(1-0.32)}{250}+\frac{0.23(1-0.23)}{175}}\\\\=0.09\pm 0.0714\\\\=(0.0186, 0.1614)\\\\\approx (0.02, 0.16)](https://tex.z-dn.net/?f=%3D%280.32-0.23%29%5Cpm%201.645%5Ctimes%5Csqrt%7B%5Cfrac%7B0.32%281-0.32%29%7D%7B250%7D%2B%5Cfrac%7B0.23%281-0.23%29%7D%7B175%7D%7D%5C%5C%5C%5C%3D0.09%5Cpm%200.0714%5C%5C%5C%5C%3D%280.0186%2C%200.1614%29%5C%5C%5C%5C%5Capprox%20%280.02%2C%200.16%29)
There will be no difference between the two proportions if the 90% confidence interval consists of 0.
But the 90% confidence interval does not consists of 0.
Thus, there is a significant difference between the two proportions.
Answer:
Given the ratio for dinosaur stamps to airplane stamp, the correct ratio is 18 : 12
Step-by-step explanation:
Dinosaur stamps = 18
Airplane stamps = 12
John wrote:
ratio of dinosaur stamps to airplane stamps = 12 to 18
Correct ratio:
ratio of dinosaur stamps to airplane stamps = 18 : 12
= 18/12
Answer:
![\frac{4}{11}](https://tex.z-dn.net/?f=%5Cfrac%7B4%7D%7B11%7D)
Step-by-step explanation:
The reciprocal of a number n is ![\frac{1}{n}](https://tex.z-dn.net/?f=%5Cfrac%7B1%7D%7Bn%7D)
Given
2
← convert to an improper fraction
= ![\frac{11}{4}](https://tex.z-dn.net/?f=%5Cfrac%7B11%7D%7B4%7D)
Reciprocal is
= ![\frac{4}{11}](https://tex.z-dn.net/?f=%5Cfrac%7B4%7D%7B11%7D)
The answer is C.) at 99.7%
In order to be able to consider this a valid null hypothesis is to accept the fact there is no significant difference between the two subject population, this statement is true for inferential statistics.. In this case the water consumption in the two district has a confidence interval should be chosen with respect to what is the closest to 100%.
Answer:
sorry if theyre wrong but i think it is
7) m<4 = x
9) m<1 = 120
Step-by-step explanation: