Using the z-distribution, we have that:
a) The 90% confidence interval for the proportion of all U.S. adults who could name all three branches of government is (0.339, 0.381). It means that we are 90% sure that the true population proportion is within these values.
b) The entire confidence interval is below 50%, which means that it provides convincing evidence that less than half of all U.S. adults could name all three branches of government.
<h3>What is a confidence interval of proportions?</h3>
A confidence interval of proportions is given by:
In which:
- is the sample proportion.
Item a:
For the parameters, we have that:
- 36% of adults in the United States could name all three branches of government, hence .
- Sample of 1416 adults, hence .
- 90% confidence level, hence, z is the value of Z that has a p-value of , so .
The lower limit of this interval is:
The upper limit of this interval is:
The 90% confidence interval for the proportion of all U.S. adults who could name all three branches of government is (0.339, 0.381). It means that we are 90% sure that the true population proportion is within these values.
Item b:
The entire confidence interval is below 50%, which means that it provides convincing evidence that less than half of all U.S. adults could name all three branches of government.
More can be learned about the z-distribution at brainly.com/question/15850972
⇒To get the difference we subtract.
⇒To get the sum we add.
Goodluck!!
The vertex of the parabola is (0,4), because you can use -b/2a to find the x coordinate a of the vertex. There is no b so b=0 and 0/anything is 0. Then you can plug 0 into the equation to find the y coordinate of the vertex. When you plug in 0 you get 4, so the vertex is (0,4)
Answer:
2,1 is the right answer
Step-by-step explanation:
hope it helps
I’m pretty sure it’s c but I’m sorry if it’s not