Answer:
(1.218 ; 1.322)
the confidence interval is appropriate
Step-by-step explanation:
The confidence interval :
Mean ± margin of error
Sample mean = 1.27
Sample standard deviation, s = 0.80
Sample size, n = 914
Since we are using tbe sample standard deviation, we use the T table ;
Margin of Error = Tcritical * s/√n
Tcritical at 95% ; df = 914 - 1 = 913
Tcritical(0.05, 913) = 1.96
Margin of Error = 1.96 * 0.80/√914 = 0.05186
Mean ± margin of error
1.27 ± 0.05186
Lower boundary = 1.27 - 0.05186 = 1.218
Upper boundary = 1.27 + 0.05186 = 1.322
(1.218 ; 1.322)
According to the central limit theorem, sample means will approach a normal distribution as the sample size increases. Hence, the confidence interval is valid, the sample size of 914 gave a critical value at 0.05 which is only marginally different from that will obtained using a normal distribution table. Hence, the confidence interval is appropriate
positive number times negative number is negative number "(+)(-) = (-)".

we change the mixed numbers to the improper fractions

Answer:

Step-by-step explanation:
I believe this is the correct answer. In order to check that my equations are correct I put in some dummy numbers.
a= 2
b=4
c= 
<span>I believe the answer is 60.75pi, calculated as follows:</span>
Area of Circle: (9 * 9) * pi = 81pi
Area of Shaded Area = (90 / 360) * 81p = 20.25pi
81pi - 20.25pi = 60.75pi
A piece-wise function combines more than one functions of different input values.
<em>The value of f(-1) is -3</em>
From the graph, we have the following observations
- <em>When x = -1, y = -3</em>
- <em>When x = -1, y = -4</em>
Notice that there is a closed circle at the point where x = -1 and y = -3.
This means that y = -3 is inclusive of the values of y on that particular function
However, there is an open circle at the point where x = -1 and y = -3.
This means that y = -4 is exclusive of the values of y on that particular function
The correct corresponding value of y is when y is inclusive.
Hence, the value of f(-1) is -3
See attachment for the graph of the piece-wise functions
Read more about piece-wise functions at:
brainly.com/question/11547854