The combined mean of the 14 people's index finger is: 12.75 cm.
<h3>How to Find the Combined Mean?</h3>
Combined mean = [(mean of first group × number of data of the first group) + (mean of second group × number of data of the second group)] ÷ (number of data of the first group + number of data of the second group).
Given the following:
Mean of first group = 7.8
Number of data of the first group = 7
Mean of second group = 17.7
Number of data of the second group = 7
Combined mean = [(7.8 × 7) + (17.7 × 7)] / (7 + 7)
Combined mean = 178.5 / 14
Combined mean = 12.75 cm.
Learn more about combined mean on:
brainly.com/question/16553735
#SPJ1
Answer:
A sample of 801 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 z-score that has a p-value of
.
The margin of error is of:
![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 p-value of
, so
.
25% of U.S. homes have a direct satellite television receiver.
This means that ![\pi = 0.25](https://tex.z-dn.net/?f=%5Cpi%20%3D%200.25)
How large a sample is necessary to estimate the true population of homes which do with 95% confidence and within 3 percentage points?
This is n for which M = 0.03. So
![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{0.25*0.75}{n}}](https://tex.z-dn.net/?f=0.03%20%3D%201.96%5Csqrt%7B%5Cfrac%7B0.25%2A0.75%7D%7Bn%7D%7D)
![0.03\sqrt{n} = 1.96\sqrt{0.25*0.75}](https://tex.z-dn.net/?f=0.03%5Csqrt%7Bn%7D%20%3D%201.96%5Csqrt%7B0.25%2A0.75%7D)
![\sqrt{n} = \frac{1.96\sqrt{0.25*0.75}}{0.03}](https://tex.z-dn.net/?f=%5Csqrt%7Bn%7D%20%3D%20%5Cfrac%7B1.96%5Csqrt%7B0.25%2A0.75%7D%7D%7B0.03%7D)
![(\sqrt{n})^2 = (\frac{1.96\sqrt{0.25*0.75}}{0.03})^2](https://tex.z-dn.net/?f=%28%5Csqrt%7Bn%7D%29%5E2%20%3D%20%28%5Cfrac%7B1.96%5Csqrt%7B0.25%2A0.75%7D%7D%7B0.03%7D%29%5E2)
![n = 800.3](https://tex.z-dn.net/?f=n%20%3D%20800.3)
Rounding up:
A sample of 801 is needed.
The correct option is D. In fact, you can evaluate this function at every possible input x.
All this function does is:
- Take a number x
- Add 6
- If the result is negative switch the sign, otherwise keep it as it is
As you can see, you can perform these operations regardless of the input x.
Answer:
2/3 cup of pineapple juice for 1/3 cup of orange juice to make 1 smoothie
Let the no. Of smoothies be x
x/3 = 111
x = 333 smoothies
Cups of pineapple juice = 222
Hope this helps!
<span>it is an implicit function, (for high school students)
1) d(4x2+y2)/dx=d(48+2xy)/dx, after the differentiation, we obtain
8x + 2y .dy/dx = 2y + 2x .dy/dx
</span>8x - 2y = 2x .dy/dx - 2y .dy/dx, 4x - y = (x .- y ).dy/dx, and then
dy/dx = y-4x / y - x
2) when x cordinate is 2
we have 4(2^2) + y^2 = 48 + 2 . 2 y, and the y^2 - 4y - 32=0, after solving the quadratic equation we find y = - 8, or y = 4, this the positive y coordinate, the answer is y = 4
3) Let be P (xp, yp) the point, since P is the point at which the line tangent to the curve at P is horizontal, so we can write 4xp2+yp2=48+2xpyp, but xp=2, we have yp^2 - 4yp - 32=0, so P(2, 4)