Answer:
128
Step-by-step explanation:
You start out with one point on day one. The second day, your points are doubled. Each day after that is doubled from the previous day. So, the second day, you have 2 points. Multiply that by 2 to get 4 for day three.
Day four:4 x 2 = 8.
Day five: 8 x 2 = 16.
Day six: 16 x 2 = 32
Day seven: 32 x 2 = 64
Day eight: 64 x 2 = 128
X + x - 8 + x/2 - 4 = 38
2x + x/2 = 38 + 8 + 4
5x/2 = 50
5x = 100
x = 20
that the amoint of water : 20
amount of rubbing alcohol: (1/2)(20-8) = (1/2)(12) = 6
difference : 20-6 = 14
hope this help
I got A as my answer... 8 1/3 also = 25/3 and if you multiply 25/3 x 4.5 then you get A
Answer:
English??
Step-by-step explanation:
Answer:
A sample size of 657 is needed.
Step-by-step explanation:
In a sample with a number n of people surveyed with a probability of a success of
, and a confidence level of
, we have the following confidence interval of proportions.
![\pi \pm z\sqrt{\frac{\pi(1-\pi)}{n}}](https://tex.z-dn.net/?f=%5Cpi%20%5Cpm%20z%5Csqrt%7B%5Cfrac%7B%5Cpi%281-%5Cpi%29%7D%7Bn%7D%7D)
In which
z is the zscore that has a pvalue of
.
The margin of error is:
![M = z\sqrt{\frac{\pi(1-\pi)}{n}}](https://tex.z-dn.net/?f=M%20%3D%20z%5Csqrt%7B%5Cfrac%7B%5Cpi%281-%5Cpi%29%7D%7Bn%7D%7D)
95% confidence level
So
, z is the value of Z that has a pvalue of
, so
.
In the past, 19% of all homes with a stay-at-home parent had the father as the stay-at-home parent.
This means that ![\pi = 0.19](https://tex.z-dn.net/?f=%5Cpi%20%3D%200.19)
(a) What sample size is needed if the research firm's goal is to estimate the current proportion of homes with a stay-at-home parent in which the father is the stay-at-home parent with a margin of error of 0.03?
A sample size of n is needed.
n is found when ![M = 0.03](https://tex.z-dn.net/?f=M%20%3D%200.03)
Then
![M = z\sqrt{\frac{\pi(1-\pi)}{n}}](https://tex.z-dn.net/?f=M%20%3D%20z%5Csqrt%7B%5Cfrac%7B%5Cpi%281-%5Cpi%29%7D%7Bn%7D%7D)
![0.03 = 1.96\sqrt{\frac{0.19*0.81}{n}}](https://tex.z-dn.net/?f=0.03%20%3D%201.96%5Csqrt%7B%5Cfrac%7B0.19%2A0.81%7D%7Bn%7D%7D)
![0.03\sqrt{n} = 1.96\sqrt{0.19*0.81}](https://tex.z-dn.net/?f=0.03%5Csqrt%7Bn%7D%20%3D%201.96%5Csqrt%7B0.19%2A0.81%7D)
![\sqrt{n} = \frac{1.96\sqrt{0.19*0.81}}{0.03}](https://tex.z-dn.net/?f=%5Csqrt%7Bn%7D%20%3D%20%5Cfrac%7B1.96%5Csqrt%7B0.19%2A0.81%7D%7D%7B0.03%7D)
![(\sqrt{n})^{2} = (\frac{1.96\sqrt{0.19*0.81}}{0.03})^{2}](https://tex.z-dn.net/?f=%28%5Csqrt%7Bn%7D%29%5E%7B2%7D%20%3D%20%28%5Cfrac%7B1.96%5Csqrt%7B0.19%2A0.81%7D%7D%7B0.03%7D%29%5E%7B2%7D)
![n = 656.91](https://tex.z-dn.net/?f=n%20%3D%20656.91)
Rounding up to the nearest whole number.
A sample size of 657 is needed.