Answer:
This is an observational study based on a stratified sample.
Step-by-step explanation:
This study aimed to check which clean-up/drying up method after handwashing was more effective; that is, do dryers eliminate more germs than paper towels.
It involved 100 people that took part in the study. The 100 of them contaminated their hands and were instructed to wash their hands with soap and water for 15 seconds before the participants are randomly grouped into two strata; one stratum/group (consisting of 50 participants) that dries their hands with a dryer and another (also consisting of 50 participants) that dry their hands with paper towels.
An observational study is one in which data is collected only by monitoring the events of the study. The conductor of the study in no way tries to intervene or control any of the variables being studied. No control, no tweaking of factors, just observe and record data.
An observational study based on a stratified sample is an observational study that uses the stratified sampling method to carry out its objectives. It randomly puts each of the participants being observed into groups or strata. Each group of randomly assigned participants are then required to run the test for one of the variables being compared.
This is exactly what the study in the question describes. This is why this study is undoubtedly an observational study based on a stratified sample.
Hope this Helps!!!
Answer:
Vertical : Angles 1 & 4 Supplementary: 5 & 6
Step-by-step explanation:
Vertical angels are angles that have the same measure that are opposites of each other (1 & 4) and supplementary angles are 2 angles that equal 180 degrees that are right next to each other or right above each other (5 & 6) (3 & 5)
Answer:
A= 0.5, B=2.2, C=0.12, D=.0.9.
Step-by-step explanation:
Answer:
Action verb
Step-by-step explanation:
Reported is an action verb
Answer:
The 95% confidence interval for the population proportion of tenth graders reading at or below the eighth grade level is (0.2087, 0.2507).
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 
.
For this problem, we have that:
Suppose a sample of 1537 tenth graders is drawn. Of the students sampled, 1184 read above the eighth grade level. So 1537 - 1184 = 353 read at or below this level. Then
95% confidence level
So 
, z is the value of Z that has a pvalue of 
, so 
.
The lower limit of this interval is:
The upper limit of this interval is:
The 95% confidence interval for the population proportion of tenth graders reading at or below the eighth grade level is (0.2087, 0.2507).
