too much math for my mental health
Answer:
test statistic (Z) is 2.5767 and p-value of the test is .009975
Step-by-step explanation:
: percentage of students who smoke did not change
: percentage of students who smoke has changed
z-statistic for the sample proportion can be calculated as follows:
z=
where
- p(s) is the sample proportion of smoking students (
=0.25)
- p is the proportion of smoking students in the survey conducted five years ago (18% or 0.18)
- N is the sample size (200)
Then, z=
≈ 2.5767
What is being surveyed is if the percentage of students who smoke has changed over the last five years, therefore we need to seek two tailed p-value, which is .009975.
This p value is significant at 99% confidence level. Since .009975 <α/2=0.005, there is significant evidence that the percentage of students who smoke has changed over the last five years
Answer:
Riley divided the number of petunia seeds by the number of begonia seeds, getting
. What you actually need to do to calculate the probability of selecting a petunia seed is divide the number of petunia seeds by the <em>total</em> number of seeds. 5 petunia seeds and 15 begonia seeds makes 20 total seeds, so you divide 5 petunia seeds by 20 total seeds to get
.
X + x + 1 + x + 2 + x + 3 = 330
4x + 6 = 330
4x = 324, x = 81
Smallest number: 81
Biggest number: 81 + 3 = 84
Sum: 81 + 84 = 165
The answer is 165