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.
<span>5t=3b+660....and ... 2t+5b=450
from the first we can see that t=(3b+660)/5 and using this value in the second...
(6b+1320)/5+5b=450 making all have common denominator..
6b+1320+25b=2250
31b=930
b=30...and since 2t+5b=450
t=150</span>
Answer:
The probability of getting 2 socks of the same color is 1/3.
Step-by-step explanation:
In the drawer,
Number of blue socks = 4
Number of white socks = 8
Number of gray socks = 4
Total number of socks = 4 + 8 + 4 = 16
Total ways to select 2 socks form 16 socks is

Total ways to select 2 socks of the same color is
T = Possible ways of (2 blue + 2 white +2 gray) socks
= 
= 
= 
The probability of getting 2 socks of the same color is



Therefore, the probability of getting 2 socks of the same color is 1/3.
Excuse me, is this I ready because you know you can get reported right... just try your best, it's not a real grade! :)
& possibly delete this question because a bot can track and report this to your school. People at my school did that and got in 3 days detention...