SWBAT: Review all Chi-Square Tests
Lesson 11-5 REVIEW
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SWBAT: Review all Chi-Square Tests
Lesson 11-5 REVIEW
1. An experiment in chicken breeding results in offspring having very curly, slightly curly, or
normal feathers. If this is the result of a single gene system, then the proportions of offspring in
the three phenotypes should be 0.25, 0.50 and 0.25 respectively. In one such experiment, 93
chickens were born. 20 had normal feathers, 50 had slightly curly feathers, and 23 had very
curly feathers. C arry out a test to determine whether the genetic model seems to hold in this
setting.
SWBAT: Review all Chi-Square Tests
Lesson 11-5 REVIEW
2. In a randomly selected telephone survey of 800 registered voters, the data are classified both
by gender of respondent and by respondent’s opinion on an environmental bond issue.
Men
Women
Bond Issue
For
450
160
Against
150
40
We want to know whether there is good evidence that one’s gender influences whether a person
is for or against the bond issue. Use the chi-square test to answer this question. State the
hypotheses, discuss conditions, perform calculations, and report your conclusions.
SWBAT: Review all Chi-Square Tests
Lesson 11-5 REVIEW
3. Do male and female college students have the same distribution of living conditions? Use a
level of significance of 0.05. Suppose that 250 randomly selected male college students and 300
randomly selected female college students were asked about their living conditions: Dorm,
Apartment, With Parents, Other. The results are shown in the table below:
Male
Female
Dorm
72
91
Apartment
84
86
With Parents
49
88
Other
45
35
SWBAT: Review all Chi-Square Tests
Lesson 11-5 REVIEW
4. A company says its premium mixture of nuts contains 10% Brazil nuts, 20% cashews, 20%
almonds, and 10% hazelnuts, and the rest are peanuts. You buy a large can and separate the
various kinds of nuts. Upon weighing them, you find there are 112 grams of Brazil nuts, 183
grams of cashews, 207 grams of almonds, 71 grams of hazelnuts, and 446 grams of peanuts.
You wonder whether your mix is significantly different from what the company advertises.
Explain why the chi-square goodness-of-fit test is not an appropriate way to find out.
5. Two difference cereal companies each make a bran cereal, a corn cereal, and a rice cereal.
Each person in a random sample of 300 potential customers tasted all six cereals and selected
their favorite. The choice was then classified according to type of cereal and the company that
made the cereal. The data is shown in the table below. What type of test would be appropriate?
(A) C hi-square goodness-of-fit test
(B) C hi-square test of independence
(C) Chi-square test of homogeneity
(D) Either a chi-square test for independence or homogeneity is appropriate
(E) A chi-square test is not appropriate in this situation
6. A cupcake store manager believes that half of the cupcakes sold are chocolate and that
the other half is equally divided between vanilla and cherry. If the manager's belief is
correct and 300 cupcakes are sold, how many would you expect to be cherry cupcakes?
(A) 300
(B) 200
(C) 150
(D) 100
(E) 75
7. A local bagel shop makes six types of bagels and eight types of cream cheese toppings.
Suppose that all customers order one type of bagel and one type of cream cheese. If
customers are classified according to the type of bagel and type of cream cheese, how
many degrees of freedom would be appropriate for a test to determine if there is an
association between type of bagel and type of cream cheese purchased?
(A) 7
(B) 12
(C) 14
(D) 35
(E) 48