2 equal 4 Answer:
Step-by-step explanation:
x+3x+3x=21
7x=21
x=3
3, 9, 9=21
the answers are 3, 9, and 9
4 hours for 18
7 hours for 25.50
Difference in hours: 7-4 = 3
Difference in cost: 25.50 - 18 = 7.50
7.50 / 3 = 2.50
A. They charge 2.50 per hour.
B. 2.50 x 4 = 10
18 - 10 = 8
The flat fee is 8 dollars
C. 8 + (2 x 2.50) = 13 dollars
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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Answer:
Step-by-step explanation:
Let the office charge = x
Amount paid by Medicare = ⅞x
Amount paid by Ross = ¼(⅞x) = $262.50
Solve for x
Check:
OK.
