Answer:
36 Teachers in Total
Step-by-step explanation:
I would use Ratio.
Students: 128 + 121 + 135 = 384 total students
Teachers: Students
3 : 32
36 : 384
384 ÷ 32 = 12
12 x 3 = 36
Step-by-step explanation:
logx√2=1/6
<=> logx(2^1/2)=1/6
<=>1/2.logx(2)=1/6
<=>logx(2)=1/3
<=>2=x^1/3
<=>x=
Sorry I forgot the formula in the last step
Answer:
Step-by-step explanation:
Hello!
For me, the first step to any statistics exercise is to determine what is the variable of interest and it's distribution.
In this example the variable is:
X: height of a college student. (cm)
There is no information about the variable distribution. To estimate the population mean you need a variable with at least a normal distribution since the mean is a parameter of it.
The option you have is to apply the Central Limit Theorem.
The central limit theorem states that if you have a population with probability function f(X;μ,δ²) from which a random sample of size n is selected. Then the distribution of the sample mean tends to the normal distribution with mean μ and variance δ²/n when the sample size tends to infinity.
As a rule, a sample of size greater than or equal to 30 is considered sufficient to apply the theorem and use the approximation.
The sample size in this exercise is n=50 so we can apply the theorem and approximate the distribution of the sample mean to normal:
X[bar]~~N(μ;σ2/n)
Thanks to this approximation you can use an approximation of the standard normal to calculate the confidence interval:
98% CI
1 - α: 0.98
⇒α: 0.02
α/2: 0.01
![Z_{1-\alpha /2}= Z_{1-0.01}= Z_{0.99} =2.334](https://tex.z-dn.net/?f=Z_%7B1-%5Calpha%20%2F2%7D%3D%20Z_%7B1-0.01%7D%3D%20Z_%7B0.99%7D%20%3D2.334)
X[bar] ± ![Z_{1-\alpha /2} * \frac{S}{\sqrt{n} }](https://tex.z-dn.net/?f=Z_%7B1-%5Calpha%20%2F2%7D%20%2A%20%5Cfrac%7BS%7D%7B%5Csqrt%7Bn%7D%20%7D)
174.5 ± ![2.334* \frac{6.9}{\sqrt{50} }](https://tex.z-dn.net/?f=2.334%2A%20%5Cfrac%7B6.9%7D%7B%5Csqrt%7B50%7D%20%7D)
[172.22; 176.78]
With a confidence level of 98%, you'd expect that the true average height of college students will be contained in the interval [172.22; 176.78].
I hope it helps!
Answer:
The diameter of the circle O is <em>12 units</em>
Step-by-step explanation:
There is no data in the image provided. To better help you, I'm assuming we have an arbitrary value of
![BC=6\sqrt{2}](https://tex.z-dn.net/?f=BC%3D6%5Csqrt%7B2%7D)
and the triangle B0C is right
<u>Relations in the Circle</u>
The diameter (D) is twice the radius (r) and the radius is the distance measured from the center of the circle to any point of the circumference.
Since the triangle B0C has a right angle, BD is the hypotenuse and 0B=0C=r
Applying Pythagoras's theorem:
![BC^2=r^2+r^2=2r^2](https://tex.z-dn.net/?f=BC%5E2%3Dr%5E2%2Br%5E2%3D2r%5E2)
Thus we have
![2r^2=(6\sqrt{2})^2](https://tex.z-dn.net/?f=2r%5E2%3D%286%5Csqrt%7B2%7D%29%5E2)
![2r^2=72](https://tex.z-dn.net/?f=2r%5E2%3D72)
![r^2=36](https://tex.z-dn.net/?f=r%5E2%3D36)
![r=6](https://tex.z-dn.net/?f=r%3D6)
The diameter of the circle O is D=2(6) = 12 units