Answer:
The 90% confidence interval for the mean combined fuel economy for Ford Explorers is between 22.95 and 23.63 mpg.
Step-by-step explanation:
We have the standard deviation for the sample, which means that the t-distribution is used to solve this question.
The first step to solve this problem is finding how many degrees of freedom, we have. This is the sample size subtracted by 1. So
df = 16 - 1 = 15
90% confidence interval
Now, we have to find a value of T, which is found looking at the t table, with 15 degrees of freedom(y-axis) and a confidence level of 
. So we have T = 1.7531
The margin of error is:
In which s is the standard deviation of the sample and n is the size of the sample.
The lower end of the interval is the sample mean subtracted by M. So it is 23.29 - 0.34 = 22.95 mpg
The upper end of the interval is the sample mean added to M. So it is 23.29 + 0.34 = 23.63 mpg
The 90% confidence interval for the mean combined fuel economy for Ford Explorers is between 22.95 and 23.63 mpg.
The regression equation for the data given is y= -8.57 -2.31x
Step-by-step explanation:
The first step is to form a table as shown below;
x y xy x² y²
1 4 4 1 16
2 1 2 4 1
3 5 15 9 25
4 10 40 16 100
5 16 80 25 256
6 19 114 36 361
7 15 105 49 225
28 60 360 140 984 ------sum
A linear regression equation is in the form of y=A+Bx
where ;
x=independent variable
y=dependent variable
n=sample size/number of data points
A and B are constants that describe the y-intercept and the slope of the line
Calculating the constants;
A=(∑y)(∑x²) - (∑x)(∑xy) / n(∑x²) - (∑x)²
A=(60)(140) - (28)(360) / 7(140)-(28)²
A=8400 - 10080 /980-784
A= -1680/196
A= - 8.57
B= n(∑xy) - (∑x) (∑y) / n(∑x²) - (∑x)²
B= 7(360)-(28)(60) / 7(60) - (28)²
B=2520 - 1680 /420-784
B=840/-364
B= -2.31
y=A+Bx
y= -8.57 -2.31x
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Regression equation :brainly.com/question/12280902
Keywords : equations, regression line, data
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Answer:
C because product means to multiply
We have a right triangle. We know the hypotenuse (75 ft) and an angle of 35°. We need to find the opposite leg to the angle of 35° (h). The trigonometric function that relates the opposite leg to an angle with the hypotenuse is sine:
sin 35° = (Opposite leg to 35°) / hypotenuse
sin 35° = h/(75 ft)
Solving for h:
(75 ft) sin 35°=h
h=75 sin 35° ft
h=75 (0.573576436) ft
h=43.01823270 ft
h=43 ft
Answer: T<span>he bottom of the balloon is 43 ft from the ground</span>
We know that
step 1
if ∡YWZ=17°
then
∡XWZ=17°*2-----> 34°----> because triangle XWY and triangle YWZ are congruents
step 2
∡WXY=∡WZY-------> because triangle XWY and triangle YWZ are congruents
we know that
<span>the sum of the internal angles of a triangle is 180 degrees
</span>so
180°=∡XWZ+2*∡WXY---------> ∡WXY=[180-∡XWZ]/2
∡WXY=[180-34°]/2-------> ∡WXY=73°
the answer is
∡WXY=73°
