Answer:
For this case the confidence interval is given by :

Step-by-step explanation:
Data provided
represent the sample mean for the fuel efficiencies
population mean
s=2.51 represent the sample standard deviation
n=601 represent the sample size
Confidence interval
The formula for the confidence interval of the true mean is given by:
(1)
The degrees of freedom for this case is given by:
The Confidence level for this case is 0.95 or 95%, and the significance level
and
and the critical value is given by
Replcing into the formula for the confidence interval is given by:
For this case the confidence interval is given by :

Answer:
We set up 2 equations
A) C + A = 100
B) 5C + 12A = 780
We multiply A by -5
A) -5C -5A = -500 then we add B
B) 5C + 12A = 780
7A = 280
Number of Adults = 40
5C = 780 - 40*12
5C = 780 -480
5C = 300
Number of Children = 60
Step-by-step explanation:
Answer:
-19
Step-by-step explanation:
It's -19 I took the test
Proof in the picture below
Lines BC, AB, and then AC
X = Tan^-1(15/13)
X = 49.1