Answer: 
Step-by-step explanation:
The confidence interval for population mean is given by :-
Given : Sample size : 
, which is a large sample , so we apply z-test .
Sample mean : 
Standard deviation : 
Significance level : 
Critical value : 
Now, a confidence interval at the 95% level of confidence will be :-
Answer: 95 units squared
Step-by-step explanation:
Rectangle of 10*4=40
Rectangle of 5*7=35
Triangle of 4*10/2=20
40+20+35=95
With a square or rectangular shape, the formula for figuring out how big an area is is simple: multiply the length and width of the shape by the square feet is the surface area of a pool that is feet long and feet wide (8x 10).
<span>x in (-oo:+oo)
(x+20)/2 = 3*x // - 3*x
(x+20)/2-(3*x) = 0
(x+20)/2-3*x = 0
(x+20)/2+(-3*2*x)/2 = 0
x-3*2*x+20 = 0
20-5*x = 0
(20-5*x)/2 = 0
(20-5*x)/2 = 0 // * 2
20-5*x = 0
20-5*x = 0 // - 20
-5*x = -20 // : -5
x = -20/(-5)
x = 4 so x= 4</span>
