Answer:
24.6 < μ < 27.2
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 25.9 - 1.3 = 24.6 pounds.
The upper end of the interval is the sample mean added to M. So it is 25.9 + 1.3 = 27.2 pounds.
So the correct answer is:
24.6 < μ < 27.2
Answer:
12 pi
Step-by-step explanation:
volume of sphere = 4/3 pi r2
4/3 pi 3 x 3
12 pi unit square
Answer:
A sample of 16577 is required.
Step-by-step explanation:
In a sample with a number n of people surveyed with a probability of a success of
, and a confidence level of
, we have the following confidence interval of proportions.

In which
z is the z-score that has a p-value of
.
The margin of error is of:

99% confidence level
So
, z is the value of Z that has a p-value of
, so
.
She wants to estimate the proportion using a 99% confidence interval with a margin of error of at most 0.01. How large a sample size would be required?
We have no estimation for the proportion, and thus we use
, which is when the largest sample size will be needed.
The sample size is n for which M = 0.01. So






Rounding up:
A sample of 16577 is required.
Answer:
b
Step-by-step explanation:
Using the trigonometric identities
cot x =
and tan x =
thus
+ tanΘ × cosΘ
=
+
× cosΘ
= cosΘ ×
+ sinΘ
= sinΘ + sinΘ
= 2sinΘ → b
Answer:
8 to 18
Step-by-step explanation:
8 to 18