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: 419,000
Step-by-step explanation:
418,832
In the thousand's place is an 8. Next to it is an 8.
If the # is biiger than 5 it moves up. if it's 4 or less lower it.
the answer is 419,000
Answer:
see explanation
Step-by-step explanation:
The hypotenuse is the longest side thus is (4x + 1)
The legs are 2x and (4x - 1)
Using Pythagoras' theorem, then
(4x + 1)² = (2x)² + (4x - 1)² ← expanding factors
16x² + 8x + 1 = 4x² + 16x² - 8x + 1 , that is
16x² + 8x + 1 = 20x² - 8x + 1 ( subtract 20x² - 8x + 1 from both sides )
- 4x² + 16x = 0 ( multiply through by - 1 )
4x² - 16x = 0 ← factor out 4x from each term
4x(x - 4) = 0
Equate each factor to zero and solve for x
4x = 0 ⇒ x = 0
x - 4 = 0 ⇒ x = 4
Now x > 0, thus x = 4
2x = 2(4) = 8
4x - 1 = 4(4) - 1 = 16 - 1 = 15
4x + 1 = 4(4) + 1 = 16 + 1 = 17
Thus
perimeter = 8 + 15 + 17 = 40 cm
1/4=2/8
3/8-2/8=1/8
1/8 of a hour remains on the flight. ✈️
Answer:
2y² + 14y - 15
Step-by-step explanation:
(2y² + 8y - 9) - (- 6y + 6)
Remove first parenthesis and distribute second by - 1
= 2y² + 8y - 9 + 6y - 6 ← collect like terms
= 2y² + 14y - 15