Answer:
D) the standard error for her sample is 15
Step-by-step explanation:
Samantha is 95% certain that between 50% and 70% of the first year students agree that they should be able to bring a car to campus.
Here
- 95% is the confidence level.
- The range between 50% and 70% indicates 95% confidence interval.
- 60% is the average proportion of the first year students at her university think they should be able to bring a car to campus.
- 10% (0.1) is the margin of error from the mean
Since standard error can be obtained by dividing margin of error by the z-statistic of the confidence level which is 1.96. The standard error for her sample 
does not equal to 15.
Answer:
1134.62 (THE SUM OF 20 TERMS)
Step-by-step explanation:
First we write out our given information:
a8=2a2
a11=18
an is an arithmetic sequence.
Where here an means the nth term of our sequence.
What does an arithmetic sequence mean? It means to get to the next term in your sequence you add a constant (c) each time:
an+1=an+c
Equivalently:
an+1−an(n+1)−n=c
So an is of slope c (c2 is another constant):
an=cn+c2
Where here c2=a0 (Substitute in n=0 and see why that has to be the case if we let a0 exist)
Now we use the other given information to try to come up with a solution.
Let n=2:
a2=2c+c2
Let n=8, using the above equation we have:
a8=8c+c2=2a2=4c+2c2
Let n=11
a11=18
a11=11c+c2
But a11−a8=(11c+c2)−(8c+c2)=3c
Hence, a11=3c+a8
a11=3c+4c+2c2=18
a11=3c+8c+c2=18
