Mean is 11.3 and the range is 4. Dont need to add 5 for all. Just do mean for the given options and add 5 at the end. Same with the range 9-5=4. Doesn’t change when you add 5 for all
C
Answer: x=-4
Step-by-step explanation:
See attachment
Answer:
$393.50+/-$19.72
= ( $373.78, $413.22)
Therefore, the 95% confidence interval (a,b) = ($373.78, $413.22)
Step-by-step explanation:
Confidence interval can be defined as a range of values so defined that there is a specified probability that the value of a parameter lies within it.
The confidence interval of a statistical data can be written as.
x+/-zr/√n
Given that;
Mean x = $393.50
Standard deviation r = $50.30
Number of samples n = 25
Confidence interval = 95%
z value(at 95% confidence) = 1.96
Substituting the values we have;
$393.50+/-1.96($50.30/√25)
$393.50+/-1.96($10.06)
$393.50+/-$19.7176
$393.50+/-$19.72
= ( $373.78, $413.22)
Therefore, the 95% confidence interval (a,b) = ($373.78, $413.22)
The given parabola will open; Down
<h3>How to interpret a parabola curve?</h3>
In parabolic curves, if the leading coefficient is greater than zero, the parabola opens upward, and if the leading coefficient is less than zero, the parabola opens downward.
Now, we are given the equation of the parabola s;
-36y = x²
divide both sides by -36 to get;
y = -x²/36
From the above it is clear that the leading coefficient is less than zero and as such the parabola will open in the downward direction.
Read more about parabola curve at; brainly.com/question/1480401
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