Answer:
The required sample size for the new study is 801.
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:

25% of all adults had used the Internet for such a purpose
This means that 
95% confidence level
So
, z is the value of Z that has a pvalue of
, so
.
What is the required sample size for the new study?
This is n for which M = 0.03. So






Rounding up:
The required sample size for the new study is 801.
Answer:
10
Step-by-step explanation:
10. ................ ..........
Answer:
The solution would be (5, -2)
Step-by-step explanation:
To use this method, start by multiplying the second equation by -1. Then add the two equations together.
9x + 5y = 35
-2x - 5y = 0
------------------
7x = 35
x = 5
Now that we have the value of x, use it to solve either equation for y.
2x + 5y = 0
2(5) + 5y = 0
10 + 5y = 0
5y = -10
y = -2
Log[8/(36*3)]
Log[2/27]
Hope I really help you !