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
63 miles in 270 minutes will mean that nolan rides his bike at a distance of 63/270 miles in one minute.
there are 60 minutes in an hour. So to find out the distance he covers in 1 hour, 63/270 × 60 will give you 14 miles.
Since the question is asking for the average speed, nolan rides his bike at 14 miles per hour i think.
30 percentage decrease, if you need me to explain I’ll be glad to help
6x-6+6~-2x6/5 that it okay
Answer:
1470 students do not have a full-time or part-time job
Step-by-step explanation:
We have a relationship between students who have a part-time job and those who do not. The ratio is 7 out of 10 students.
Then we use this relationship as a conversion factor.
If of 10 students, 7 of them have a job, then of 4900 students, how many of them have a job?
students
Finally, those who do not have a job are:
