Answer:
-1.96312>-2.2360
Step-by-step explanation:
first find -
which is -2.2360679775
now round it to match the lenth of the other problem
-1.96312...
-2.2360...
now remember that the bigger the negitive number, the smaller it really is,
so
-1.96312>-2.2360
None of them match the answer is really (-2,2), (-4,2), and (-2,8).
I do not understand ???????????????????
I've done the first four questions. Use this method to answer the rest. For an odd number of objects find the cost of one and multiply by how many you are asked to find.
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.