Answer:
C. (36337.32, 48968.68)
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 sample mean subtracted by M. So it is 42653 - 6315.68 = 36337.32.
The upper end of the interval is the sample mean added to M. So it is 42653 + 6315.68 = 48968.68.
So the correct answer is:
C. (36337.32, 48968.68)
Answer:
what i the question i will help i promise.
Step-by-step explanation:
Answer:
The easiest approach is to realise that one hour is 3 times longer than 20 minutes. The longer the time, the more they will pave.
215 of a mile, in 20 minutes, how much in 60 minutes?#
They will pave 3 times more.
215×31=615 of a mile
615=25 of a mile
You could also use the 'unitary method' where you find out how much they pave in ONE minute (divide by 20) and them multiply by 60 to find how much in one hour.
Look at what happens:
215÷20×60
=215×120×603
=215×3 ← exactly the same maths.
=25
Answer:

Step-by-step explanation:

just multiply across
-k*7=-7k
5*5=25

hope this helps
Step-by-step explanation:
answer is in the above picture