Answer:
(a) It is an experiment.
(b) Group III has been tested to compare the effect of tea
Step-by-step explanation:
24 volunteers are randomly selected to one of the three groups.
Group I drinks two cups of hot black tea without milk
Group II drinks two cups of hot black tea with milk
Group III drinks two cups of hot water but no tea.
At the end of the month, the researchers measured the change in each of the participant's heart health.
The average change of health status of three Groups can be measured and let it be X1', X2' and X3'. We can set up the hypothesis of no difference of heart health i.e H0 : µ1 = µ2 = µ3 against the alternative hypothesis that they are not equal. As the sample size is less than 30, we can use t-statistic.
Under the above logic, (a) it is an experiment.
(b) Group III has been tested to compare the effect of tea or to have comparison between GroupI and Group III.
4/3
explanation : just write it in fraction form
Answer:
The p-value of the test statistic from the standard normal table is 0.0017 which is less than the level of significance therefore, the null hypothesis would be rejected and it can be concluded that there is sufficient evidence to support the claim that less than 20% of the pumps are inaccurate.
Step-by-step explanation:
Here, 1304 gas pumps were not pumping accurately and 5689 pumps were accurate.
x = 1304, n = 1304 + 5689 = 6993
The level of significance = 0.01
The sample proportion of pump which is not pumping accurately can be calculated as,
The claim is that the industry representative less than 20% of the pumps are inaccurate.
The hypothesis can be constructed as:
H0: p = 0.20
H1: p < 0.20
The one-sample proportion Z test will be used.
The test statistic value can be obtained as:
Answer:
3m-3n
Step-by-step explanation:
We want to simplify the expression;
2m - [n - (m - 2n)].
We expand the parenthesis to obtain;
2m - (n - m + 2n)
2m - ( - m + 3n)
Expand further to get;
2m +m -3n
Combine the first two terms;
3m-3n
have you tried 42 because it's a 90 degree triangle and 30+18+42 equals 90
