30% change Hope this helps :)
-73 i think it is i might be wrong
Answer:
Domain: (x/xER)
Range: (y/y>0)
Step-by-step explanation:
Answer:
The confidence interval at a 90% confidence level is ($43.79, $48.21).
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 , so
Now, find M as such
In which is the standard deviation of the population and n is the size of the sample.
The lower end of the interval is the mean subtracted by M. So it is 46 - 2.21 = 43.79
The upper end of the interval is the mean added to M. So it is 46 + 2.21 = 48.21.
The confidence interval at a 90% confidence level is ($43.79, $48.21).