Answer:
This question dosnt make sense
Step-by-step explanation:
Answer:
a) 752 medical files should be included.
b) 372 medical files should be included.
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)
90% confidence level
So
, z is the value of Z that has a p-value of
, so
.
Question a:
This is n for which M = 0.03. We have no estimate, so we use
. 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 = 1.645\sqrt{\frac{0.5*0.5}{n}}](https://tex.z-dn.net/?f=0.03%20%3D%201.645%5Csqrt%7B%5Cfrac%7B0.5%2A0.5%7D%7Bn%7D%7D)
![0.03\sqrt{n} = 1.645*0.5](https://tex.z-dn.net/?f=0.03%5Csqrt%7Bn%7D%20%3D%201.645%2A0.5)
![\sqrt{n} = \frac{1.645*0.5}{0.03}](https://tex.z-dn.net/?f=%5Csqrt%7Bn%7D%20%3D%20%5Cfrac%7B1.645%2A0.5%7D%7B0.03%7D)
![(\sqrt{n})^2 = (\frac{1.645*0.5}{0.03})^2](https://tex.z-dn.net/?f=%28%5Csqrt%7Bn%7D%29%5E2%20%3D%20%28%5Cfrac%7B1.645%2A0.5%7D%7B0.03%7D%29%5E2)
![n = 751.67](https://tex.z-dn.net/?f=n%20%3D%20751.67)
Rounding up:
752 medical files should be included.
Question b:
Now we have that:
![\pi = \frac{13}{90} = 0.1444](https://tex.z-dn.net/?f=%5Cpi%20%3D%20%5Cfrac%7B13%7D%7B90%7D%20%3D%200.1444)
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 = 1.645\sqrt{\frac{0.1444*0.8556}{n}}](https://tex.z-dn.net/?f=0.03%20%3D%201.645%5Csqrt%7B%5Cfrac%7B0.1444%2A0.8556%7D%7Bn%7D%7D)
![0.03\sqrt{n} = 1.645\sqrt{0.1444*0.8556}](https://tex.z-dn.net/?f=0.03%5Csqrt%7Bn%7D%20%3D%201.645%5Csqrt%7B0.1444%2A0.8556%7D)
![\sqrt{n} = \frac{1.645\sqrt{0.1444*0.8556}}{0.03}](https://tex.z-dn.net/?f=%5Csqrt%7Bn%7D%20%3D%20%5Cfrac%7B1.645%5Csqrt%7B0.1444%2A0.8556%7D%7D%7B0.03%7D)
![(\sqrt{n})^2 = (\frac{1.645\sqrt{0.1444*0.8556}}{0.03})^2](https://tex.z-dn.net/?f=%28%5Csqrt%7Bn%7D%29%5E2%20%3D%20%28%5Cfrac%7B1.645%5Csqrt%7B0.1444%2A0.8556%7D%7D%7B0.03%7D%29%5E2)
![n = 371.5](https://tex.z-dn.net/?f=n%20%3D%20371.5)
Rounding up:
372 medical files should be included.
Answer:
2:5
Step-by-step explanation:
your welcome. jsvsjgbdjshwbkshd
Answer:
![JL=54](https://tex.z-dn.net/?f=JL%3D54)
Step-by-step explanation:
We are given that K is the midpoint of JL. Using this information, we want to find JL.
By the definition of midpoint, this means that:
![JK=KL](https://tex.z-dn.net/?f=JK%3DKL)
Substitute them for their equations:
![8x+11=14x-1](https://tex.z-dn.net/?f=8x%2B11%3D14x-1)
Solve for <em>x.</em> Subtract 8<em>x</em> from both sides:
![11=6x-1](https://tex.z-dn.net/?f=11%3D6x-1)
Add 1 to both sides:
![6x=12](https://tex.z-dn.net/?f=6x%3D12)
And divide both sides by 6. Hence:
![x=2](https://tex.z-dn.net/?f=x%3D2)
JL is the sum of JK and KL. Hence:
![JK+KL=JL](https://tex.z-dn.net/?f=JK%2BKL%3DJL)
Since JK = KL, substitute either one for the other:
![JK+(JK)=2JK=JL](https://tex.z-dn.net/?f=JK%2B%28JK%29%3D2JK%3DJL)
Substitute JK for its equation:
![2(8x+11)=JL](https://tex.z-dn.net/?f=2%288x%2B11%29%3DJL)
Since we know that <em>x</em> = 2:
![2(8(2)+11)=2(16+11)=2(27)=54=JL](https://tex.z-dn.net/?f=2%288%282%29%2B11%29%3D2%2816%2B11%29%3D2%2827%29%3D54%3DJL)
Thus:
![JL=54](https://tex.z-dn.net/?f=JL%3D54)
Answer:
63 m²
Step-by-step explanation:
The area (A) of a triangle is calculated as
A =
bh ( b is the base and h the perpendicular height )
Here b = 14 and h = 9 , then
A =
× 14 × 9 = 7 × 9 = 63 m²