The college is planning to add the food vendor in student union and would like to know what kind of food service the students would prefer. A sample of 120 students is obtained and each student is asked to choose his/her preference from coffee shop, a pizza place, or hamburger grill. The resulting frequency data are given in the table below.
|
Coffee
|
Pizza
|
Hamburger
|
|
53
|
37
|
30
|
(a) Do the data point out any significant preferences among the 3 types of food service? Test at the .05 level of significance.
a) Yes, there are important preferences
b) no; there are no important preferences
(b) A similar survey of student population 10 years ago found that coffee shop was preferred through 20% of the students, and pizza and hamburger were each preferred by 40% of students. Find out the expected frequencies for chi-square test.
Coffee --------
Pizza --------
Hamburger---------
Do the data indicate a significant change in preferences during the past 10 years?
a) Yes, there has been a significant change in preferences
b) no, there hasn't been any change in the population proportions