Answer:
Step-by-step explanation:
Answer:
The 90% confidence interval for the mean usage of electricity is between 17.4 kwH and 17.6 kwH
Step-by-step explanation:
We have that to find our
level, that is the subtraction of 1 by the confidence interval divided by 2. So:

Now, we have to find z in the Ztable as such z has a pvalue of 
So it is z with a pvalue of 1-0.05 = 0.95, so z = 1.645
Now, find the margin of error M as such

In which
is the standard deviation of the population and n is the size of the sample.
So

The lower end of the interval is the mean subtracted by M. So 17.5 - 0.14 = 17.4 kwH
The upper end of the interval is M added to the mean. So 17.5 + 0.14 = 17.6 kwH
The 90% confidence interval for the mean usage of electricity is between 17.4 kwH and 17.6 kwH
Answer:
x = 7
Step-by-step explanation:
27 = 7x + 6 - 4x (Given)
27 = 3x + 6 (Simplify)
27 - 6 = 3x + 6 - 6 (Subtract 6 on both sides)
21 = 3x (Simplify)
21/3 = 3x/3 (Divide 3 on both sides)
7 = x (Simplify)
Step-by-step explanation:
do you mean x if it's x = 28/5
hope it helpful ❤❤❤
THANK YOU
Slope formula : (y2 - y1) / (x2 - x1)
(2,-2)....x1 = 2 and y1 = -2
(4,1)...x2 = 4 and y2 = 1
now we sub into the slope formula and solve for the slope
slope = (1 - (-2) / (4 - 2) = (1 + 2) / 2 = 3/2
now we use y = mx + b
slope(m) = 3/2
use either of ur points....(4,1)...x = 4 and y = 1
now sub into y = mx + b formula and find b, the y int
1 = 3/2(4) + b
1 = 6 + b
1 - 6 = b
-5 = b
so ur equation is : y = 3/2x - 5 <==