Answer:
the answer is 4
Step-by-step explanation:
idk I just found a calculator website lol
http://www.alcula.com/calculators/statistics/mean-absolute-deviation/
Using the z-distribution, we have that:
- For a 99% confidence level, a sample size of 127 is needed.
- For a 95% confidence level, a sample size of 74 is needed, meaning that a decrease in the confidence level decreases the needed sample size, as M and n are inverse proportional.
<h3>What is a z-distribution confidence interval?</h3>
The confidence interval is:
The margin of error is:
In which:
- is the sample mean.
- is the standard deviation for the population.
For a 99% confidence interval, , hence z is the value of Z that has a p-value of , so the critical value is z = 2.575.
The margin of error and population standard deviation are:
Hence we have to solve for n to find the needed sample size, as follows:
n = 126.4.
Rounding up, for a 99% confidence level, a sample size of 127 is needed.
For the 95% confidence interval, we have that z = 1.96, hence:
n = 73.3.
Rounding up, for a 95% confidence level, a sample size of 74 is needed, meaning that a decrease in the confidence level decreases the needed sample size, as M and n are inverse proportional.
More can be learned about the z-distribution at brainly.com/question/25890103
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108 miles 3 hours = 36 mph upstream
108 miles 2 hours = 54 mph downstream
bv = boat velocity in still water
cv = current velocity
bv -cv = 36
bv +cv = 54 Adding both equations
2*bv = 90
boat velocity in still water = 45 mph
since bv + cv = 54
then we know the current velocity = 9 mph
The equation of second graph is
We have given the linear equation is
If the graph of the position of the second object is parallel to
<h3>What is the form of linear equation?</h3>
The equation of slope intercept form is
compare the given equation with the slope intercept form
we get m = 2.5
t = 0, d = 1
1 = 2.5 · 0 + b
b = 1
Therefore,the equation of second graph is
To learn more about the linear equation visit:
brainly.com/question/14323743
Step-by-step explanation:
sum of all angles in a triangle is 180 degrees
x + 3x + 13 + x - 8 = 180
5x + 5 = 180
5x = 175
x = 37°
A = 3x + 13
3(37) + 13
A = 124°