Answer:
314.2ft^2
Step-by-step explanation:
Given data
Diameter= 20ft
Radius r= 20/2= 10ft
The expression for the area is
A= πr^2
A= 3.142*10^2
A= 3.142*100
A= 314.2ft^2
Hence the area is 314.2ft^2
The confidence interval at 95% level is
7106.87 < μ< 14255.27
<h3>What is meant be mean and standard deviation?</h3>
The ratio of sum of observations to the total number of observation is known as mean. It is one of the central tendency in the statistics. It gives an idea about the central value present in the data. The most sensitive measure of central tendency is mean. It is very easy to calculate. Mean playa a crucial role in daily life. The two types of means are Arithmetic mean and Geometric mean.
Standard deviation is a measure in the statistics. The amount of variation of a set of values is known as standard deviation. Standard deviation is denoted by σ.
As per given data
90% confident level for amount of electricity used in community of Austin is
X-tx/2(n-1)s/√n < μ < X+ tx/2(n-1)s/√n
Here , n=12 , X=10681.07 , s=6893.87
Margin of error = tx/2(n-1)s/√n
=(1.796×6893.87)/√12
=3574.1996
=3574.19(approximately)
Therefore, 90% CI is,
10681.07-3574.19 ≤ μ<10681.07+3574.19
7106.87 < μ< 14255.27
To know more about mean and standard deviation, visit:
brainly.com/question/14720855
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In total 660 rolls were made in all
Answer:
9 + 5.5x
Step-by-step explanation:
