Answer:
it should be A but im not fully sure
Answer:
95% Confidence interval = (23.4,26.2)
Step-by-step explanation:
In this problem we have to develop a 95% CI for the mean.
The sample size is n=49, the mean of the sample is M=24.8 and the standard deviation of the population is σ=5.
We know that for a 95% CI, the z-value is 1.96.
The CI is
You want to find the monthly average over the past 6 months.
July: $78.56
August: $30.21
September: $81.20
October: $79.08
November: $66.18
December: $100.75
Add all of these up
(July) $78.56
(August) $30.21
(September) $81.20
(October) $79.08
(November) $66.18
(December) + $100.75
----------------------------------------------
(Total cost) $435.88
There are 6 months you are calculating for, therefore divide the total (combined) cost of 6 months with the total number of months (in this case, 6)
$435.88 (total cost of 6 months) ÷ 6 (months)
The average cost per month of over the past 6 months is $72.66.
One hundred hundredths make up one whole.
