Answer:
5
Step-by-step explanation:
because by solving that the answer comes 5.70
A ratio equivalent to 3/20 can be 6/40 or even 9/60
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:
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Answer:
B. -2x2 + 6x + 6.
Step-by-step explanation:
(2x2 + 4x + 3) - (4x2 - 2x-3) Distribute negative over the parentheses:
= 2x2 + 4x + 3 - 4x2 + 2x + 3
= 2x2 - 4x2 + 4x + 2x + 3 + 3
= -2x2 + 6x + 6.
