There is a relationship between confidence interval and standard deviation:

Where

is the mean,

is standard deviation, and n is number of data points.
Every confidence interval has associated z value. This can be found online.
We need to find the standard deviation first:

When we do all the calculations we find that:

Now we can find confidence intervals:

We can see that as confidence interval increases so does the error margin. Z values accociated with each confidence intreval also get bigger as confidence interval increases.
Here is the link to the spreadsheet with standard deviation calculation:
https://docs.google.com/spreadsheets/d/1pnsJIrM_lmQKAGRJvduiHzjg9mYvLgpsCqCoGYvR5Us/edit?usp=sharing
Answer:
Explanation:
The expression that must be rewritten as a fully simplified fraction is:
You must, first, convert
as a fraction.
The line over the decimal 4 means that the digit 4 repeats indefinetly.
To find the fraction that represents this number you follow this procedure:

Now, you can mutiply both fractions:

Answer:
700
Step-by-step explanation:
to find the range, you subtract the smaller number of the two numbers from the larger one. If there is more than two numbers, you subtract the smallest one of the group from the largest one in the group. In this situation, you do 750-50, which is 700.
Answer:
c+20=72
Step-by-step explanation:
Answer:
C
Step-by-step explanation:
3x + 3y = -x + 5y
3x + x = 5y - 3y
4x = 2y
Divide both by 2
2x = y
(1,2) when x=1, y=2
2(1)=2 is a true statement
(2,4) when x=2, y=4
2(2)=4 is a true statement