Answer:
12/13
Step-by-step explanation:
m=(-6-6)/(-7-6)=-12/-13=12/13
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.
Answer:
The appropriate hypotheses for performing a significance test is:
Step-by-step explanation:
Last year, the mean score on the state’s math test was 51. The administrators have trained the teachers in a new method of teaching math hoping to raise the scores on this standardized test this year.
At the null hypothesis, we test if the mean score this year is the same as last year, that is:
At the alternate hypothesis, we test if the mean score improved this year from last, that is:
The appropriate hypotheses for performing a significance test is:
Answer: 
<u>Step-by-step explanation:</u>
