Answer:
10 1/8 years?
I hope this is right!
Step-by-step explanation:
Is it an isosceles triangle
Answer:
Can you write in English?
Answer:
31 terms.
Step-by-step explanation:
218 = 8 + (n-1)7
210 = (n-1)7
30 + n-1
n = 31
There would be 31 terms in the given AP.
Answer:
The 98% confidence interval for the mean purchases of all customers is ($37.40, $61.74).
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 49.57 - 12.17 = $37.40.
The upper end of the interval is the mean added to M. So it is 49.57 + 12.17 = $61.74.
The 98% confidence interval for the mean purchases of all customers is ($37.40, $61.74).