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:
Isosceles or scalene
Isosceles has 2 sides that are the same value
scalene is where none of the sides are equal
Answer:
x = 3
Step-by-step explanation:
Here, we want to find the value of x
By mathematical convention;
NM = NL + LM
Now, substitute individual values
3x + 13 = (6x-5) + (2x + 3)
3x + 13 = 6x-5 + 2x + 3
3x + 13 = 8x -2
Collect like terms
8x -3x = 13 + 2
5x = 15
x = 15/5
x = 3
Answer:
The score that cuts off the bottom 2.5% is 48.93.
Step-by-step explanation:
When the distribution is normal, we use the z-score formula.
In a set with mean 
and standard deviation 
, the zscore of a measure X is given by:
The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.
In this question, we have that:
What is the score that cuts off the bottom 2.5%
This is X when Z has a pvalue of 0.025, so X when Z = -1.96.
The score that cuts off the bottom 2.5% is 48.93.
