The college is planning to add a food vender in the student union and would like to know what type of food service the students would prefer. A sample of 120 students is obtained and each student is asked to select his/her preference from a coffee shop, a pizza place, or a hamburger grill. The resulting frequency data are as follows: coffee pizza hamburger 53 37 30 What is the the df :

Identify the type of sample ( Experimental or Observational) Then tell if the sample is biased 5.The researcher stands at a shopping mall and selects the first 75 shoppers as they walk by to fill out a survey.

Dr. A. Ventura is interested in determining what kinds and how many pets people own in Bakersfield. He stands outside Petco and asks people what kind of pet they own. This is the result of his survey: dog=1; cat=2; bird=3; reptile=4; fish=5; other=6 1,1,2,2,2,1,1,3,2,3,1,1,1,2,2,4,4,2,2,1,1,1,5,4,3,4,1,1,1,2,2,6,1,1,2,2,1,2,1,2,6,3,4,5

A vaccine to prevent a severe virus was given to children within the first year of life as part of a drug study. The study reported that of the 3456bchildren randomly assigned the​ vaccine, 58 got the virus. Of the 1606 children randomly assigned the​ placebo, 46 got the virus. a. Find the sample percentage of children who caught the virus in each group. Is the sample percentage lower for the vaccine​ group, as investigators​ hoped? b. Determine whether the vaccine is effective in reducing the chance of catching the​ virus, using a significance level of 0.01.The first few steps of the​ hypothesis-testing procedure are given. Complete the procedure.

The midterm grades of randomly picked eight students in an MMW class are as follows: 84, 90, 74, 84, 83, 89, 94, 79. What is the coefficient of variation?   6.608%   7.87%   84   2.50%

Find the 55th percentile

Here are ratings (on a scale from 1 through 5) for various Super Bowl party foods. You have to decide which food is rated highest (5 is a winner and 1 a loser). Decide what type of average you will use and why.

520 students from UC Berkeley are surveyed about whether they are from Northern California, Southern California, Central California, or from another state or country. A researcher is interested in seeing if the proportion of students from each of the four regions are all the same for all UC Berkeley students. The table below shows the outcome of the survey. Fill in the expected frequencies. Frequencies of UCB Students' Home Towns Outcome Frequency Expected Frequency Northern California Southern California Central California Out of State 189 152 170 1000

In an insurance company study of the causes of 1,000 deaths, these data were obtained. Draw a pie chart to represent the data. Cause of Death                        Number of Deaths Heart disease                           432 Cancer                                     227 Stroke                                      93 Accidents                                24 Other                                      224 Total                                       1,000

A study was conducted of pleas made by 1,025 criminals. Among those criminals, 953 pled guilty, and 395 of them were sentenced to prison. Among the 72 other criminals, who pled not guilty, 59 were sent to prison. Complete (a) through (d). a. What percentage of the criminals pled guilty? % (Round to the nearest tenth as needed.) b. What percentage of the criminals were sent to prison? % (Round to the nearest tenth as needed.) c. Among those who pled guilty, what is the percentage who were sent to prison? % (Round to the nearest tenth as needed.) d. Among those who pled not guilty, what is the percentage who were sent to prison? % (Round to the nearest tenth as needed.) ←