Answer:
95% Confidence interval for the mean
Step-by-step explanation:
We have to calculate a 95% confidence interval for the mean of a finite population.
The error is multiplied by the following finite population correction factor:
The standard deviation can be estimated as
The 95% confidence interval has a z value of 1.96, so it becomes:
Answer:
$9$
Step-by-step explanation:
Given: Thea enters a positive integer into her calculator, then squares it, then presses the $\textcolor{blue}{\bf\circledast}$ key, then squares the result, then presses the $\textcolor{blue}{\bf\circledast}$ key again such that the calculator displays final number as $243$.
To find: number that Thea originally entered
Solution:
The final number is $243$.
As previously the $\textcolor{blue}{\bf\circledast}$ key was pressed,
the number before $243$ must be $324$.
As previously the number was squared, so the number before $324$ must be $18$.
As previously the $\textcolor{blue}{\bf\circledast}$ key was pressed,
the number before $18$ must be $81$
As previously the number was squared, so the number before $81$ must be $9$.
Answer:
C: 
Step-by-step explanation:
Since a = 
:
Since n = 4 :
X^2 -6x -8 is a parabola in ax^2 + bx + c form
The axis of symmetry is -b/2a = 3
The vertex is (3,f(3)) = (3,-17)
The x-intercept is f(x)= 0 where x=-1.123, 7.123
Graphing: it opens upwards
Finding the perimetre: 7x+4x-3+x=12x-3
Good luck!
