Answer:
The sample required is 
Step-by-step explanation:
From the question we are told that
The standard deviation is 
The margin of error is 
Given that the confidence level is 99% then the level of significance is mathematically evaluated as



Next we will obtain the critical value
from the normal distribution table(reference math dot armstrong dot edu) , the value is

The sample size is mathematically represented as
![n = [ \frac{Z_{\frac{\alpha }{2} } * \sigma }{E} ]^2](https://tex.z-dn.net/?f=n%20%3D%20%5B%20%5Cfrac%7BZ_%7B%5Cfrac%7B%5Calpha%20%7D%7B2%7D%20%7D%20%2A%20%20%5Csigma%20%7D%7BE%7D%20%5D%5E2)
substituting values
![n = [ \frac{ 2.58 * 9 }{2} ]^2](https://tex.z-dn.net/?f=n%20%3D%20%5B%20%5Cfrac%7B%202.58%20%2A%20%209%20%7D%7B2%7D%20%5D%5E2)

Answer:
27
Step-by-step explanation:
The width of the frame is 9. If Marcia needs it to be THREE times as long as it is wide, that would mean she would have to multiply 3 x 9 which equals 27
Answer:
24
Step-by-step explanation:
Do i need to explain ??????
Answer:
16 : 28
Step-by-step explanation:
If 12 out of the 28 pupils are female, we can calculate the number of males by subtracting the number of females from the total number of pupils.
28 - 12 = 16
So, there are 16 males in the class. Now, we know that the ratio of males : total is 16 : 28.
I hope this helps! Have a lovely day!! :)
(brainliest is much appreciated!!)
Answer: 5
Step-by-step explanation: