Here we're discussing the "nth partial sum of a geom series."
1 - r^n
The formula for that is s(n) = a(1) ---------------
1-r
We can subst. the given values and see where that takes us:
1 - (-2)^6 1 - 64
105 = a(1)*---------------- = ----------*a(1) = -21*a(1)
1-(-2) 3
105
Solving this for a(1): a(1) = --------- = -5 (answer)
-21
Answer:
The 99% confidence interval for the average length of time all car owners plan to keep their cars is between 3.85 years and 10.55 years.
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 the margin of error 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 sample mean subtracted by M. So it is 7.2 - 3.35 = 3.85 years
The upper end of the interval is the sample mean added to M. So it is 7.2 + 3.35 = 10.55 years
The 99% confidence interval for the average length of time all car owners plan to keep their cars is between 3.85 years and 10.55 years.
(11 - 9i) - (15 - 12i) Ok so first multiple the subtraction sign into the parenthesis on the right had side of it.
And you get -15 + 12i
So now you have 11 - 9i -15 + 12i Combine Like terms
-9i + 12i = 3i
11 - 15 = -4
So your answer is 3i - 4
Hope you find this to your liking
Answer:
6.5 inches
Step-by-step explanation:
It moves up about 1/2 of an inch per day, so we just multiply 13 by 1/2 and that equals 6.5 inches. I hope this helped and please mark me brainliest!
