Answer:
a) A sample size of 5615 is needed.
b) 0.012
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 zscore that has a pvalue of
.
The margin of error is:

99.5% confidence level
So
, z is the value of Z that has a pvalue of
, so
.
(a) Past studies suggest that this proportion will be about 0.2. Find the sample size needed if the margin of the error of the confidence interval is to be about 0.015.
This is n for which M = 0.015.
We have that 






A sample size of 5615 is needed.
(b) Using the sample size above, when the sample is actually contacted, 12% of the sample say they are not satisfied. What is the margin of the error of the confidence interval?
Now
.
We have to find M.



Answer:
d
Step-by-step explanation:
Answer:
Find the explanation below.
Step-by-step explanation:
Statements simply state the theorem that is to be proofed. Formal proof in logical sequence connects the hypotheses to the conclusion reached.
Statements and reasons are important because they help to breakdown a theorem, showing in steps and stages how a conclusion was reached. They provide facts that convince the observer that the theorem is indeed true.
Answer:
C. 210 miles
Step-by-step explanation:
We have been given that two cars leave Phoenix and travel along roads 90 degrees apart. Car 1 leaves 30 minutes earlier than Car 2 and averages 42 mph.
We will use distance formula and Pythagoras theorem to solve our given problem.


.
Since car 1 leaves 30 minutes before car 2, so car 2 will travel for only 3 hours when car 1 will travel for 3.5 hours.


Since both car travel along roads 90 degree apart, therefore, the distance between both cars after Car 1 has traveled 3.5 hours would be hypotenuse with legs 147 and 150.




Therefore, the both cars will be 210 miles apart and option C is the correct choice.