Complete Question
The complete question is shown on the first uploaded image
Answer:
The 95% confidence interval is 
This means that there is 95% chance that the true population mean is within this interval
Step-by-step explanation:
From the question we are told that
The sample size is n = 30
The sample mean is 
The population standard deviation is 
Given that the confidence level is 95% then the level of confidence is evaluate as


Next we obtain the critical value of
from the normal distribution table , the values is

Generally the margin of error is mathematically represented as

substituting values


The 95% confidence interval is mathematically represented as

substituting values


Answer:
See solution below.
Step-by-step explanation:
Let's call one number x and one number y.
x/2=y
x+y=57
We can set these equations equal to each other to solve for the numbers by subtracting x from both sides of the second equation. Now the equations are:
y=-x+57 and x/2=y
Since both equations equal y, they are also equal to each other:
-x+57=x/2
First, multiply both sides by 2:
-2x+114=x
Add 2x to both sides.
114=3x
Divide both sides by 3.
38=x
One of the numbers is 38. Now, we can plug 38 in for x in either of the equations to solve for y:
(38)+y=57
Subtract 38 from both sides:
y=19
The two numbers are 38 and 19.
I hope this helps :)
Answer:
1289.8089172
Step-by-step explanation:
if you do 90 x 2 = 180 you get the circumference of what would be the complete circle, the formula for area with circumference is A = (C^2/4x3.14) so inserting 180, the answer is 2579.61783439, and half of that is a semi circle so 2579.61783439/2 = 1289.8089172