3x+2y = -7 solve for x any y using substitution
1 answer:
You might be interested in
The distance formula is shown here. If you plug your coordinates into the formula, you will get d=square root of (5-3)^2+(8-10)^2 which equals 2.828
Answer:
Critical value: z = 1.28
The 80% confidence interval for the mean repair cost for the washers is between $46.487 and $82.033.
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 1-0.1 = 0.9, so z = 1.28
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 64.26 - 17.773 = $46.487.
The upper end of the interval is M added to the mean. So 64.26 + 17.773 = $82.033.
The 80% confidence interval for the mean repair cost for the washers is between $46.487 and $82.033.