Two different analytical methods were used to determine residual chlorine in sewage effluents. Both methods were used on the same samples, but each ca

In how many ways can 7 graduate students be assigned to 1 triple and 2 double hotel rooms during a conference

Solve the following problems applying Polya’s Four-Step Problem-Solving strategy.
If six people greet each other at a meeting by shaking hands with one another, how many handshakes take place?

Effects of an appetite suppressant. Subject with preexisting cardiovascular symptoms who were receiving sibutramine, an apperite suppressant, were found to be at increased risk of cardiovascular events while taking the drug. The study included 9804 overweight or obese subjects with preexisting cardiovascular disease and/or type 2 diabetes. The subjects were randomly assigned to sibutramine (4906 subjects) or a placebo (4898 subjects) in a double-blind fashion. The primary outcome measured was the occurence of any of the following events: nonfatal myocardial infraction or stroke, resuscitation after cardiac arrest, or cardiovascular death. The primary outcome was observed in 561 subjects in the sibutramine group and 490 subjects in the placebo group.
a) Find the proportion of subjects experiencing the primary outcome for both the sibutramine and placebo groups.
b) Can we safely use the large-sample confidence interval for comparing the proportions of sibutramine and placebo subjects who experienced the primary outcome? Explain.

Researchers wanted to compare the effectiveness of a water softener used with a filtering process with a water softener used without filtering. Ninety locations were randomly divided into two groups of equal size. Group A locations used a water softener and the filtering process, while group B used only the water softener. At the end of three months, a water sample was tested at each location for its level of softness. (Water softness was measured on a scale of 1 to 5, with 5 being the softest water.) The results were as follows: Group A (water softener and filtering) ${\displaystyle x_1=2.1}$
${\displaystyle s_1=0.7}$ Group B (water softener only) ${\displaystyle x_2=1.7}$
${\displaystyle s_2=0.4}$ Determine, at the 90% confidence level, whether there is a difference between the two types of treatments.

Iranian researchers studied factors affecting patients’ likelihood of wearing orthodontic appliances, noting that orthodontics is perhaps the area of health care with the highest need for patient cooperation (Behenam & Pooya, 2007). Among their analyses, they compared students in primary school, junior high school, and high school. The data that follow have almost exactly the same means as the researchers found in their study, but with far smaller samples. The score for each student is his or her daily hours of wearing the orthodontic appliance. Did age of students impact how long they wore the orthodontic appliance for? Use alpha of .05.
Primary school: ${\displaystyle 16,13,18(M=15.67,s=2.52)}$
Junior high school: ${\displaystyle 8,13,14,12(M=11.75,s=2.63)}$
High school: ${\displaystyle 20,15,16,18(M=17.25,s=2.22)}$

a) Explain whether it is possible to use inferential methods for independent samples.
b) Explain whether there is enough information to compare the proportions using dependent samples or not.

a) Explain whether the situation involves comparing proportions for two groups or comparing two proportions from the same group.
Also, check whether the methods of the section apply to the difference in proportions.
b) Explain whether the situation involves comparing proportions for two groups or comparing two proportions from the same group. Also, check whether the methods of the section apply to the difference in proportions.
c) Explain whether the situation involves comparing proportions for two groups or comparing two proportions from the same group. Also, check whether the methods of the section apply to the difference in proportions.
d) Explain whether the situation involves comparing proportions for two groups or comparing two proportions from the same group. Also, check whether the methods of the section apply to the difference in proportions.