Science Institute Statistical Analysis

Mrs. Speirs

Name __________________________________________ Period ____

Directions: Using the sample data and a 0.05 significance level, test the claim that the color distribution is as claimed by Mars, Inc.

Problem

Mars, Inc. claims that its M&M plain candies are distributed with the color percentages of 30% brown, 20% yellow, 20% red, 10% orange, 10% green, and 10% blue. The colors of the M&Ms listed are summarized in Table 10-4.

Frequencies of M&M Plain Candies

 

Brown

Yellow

Red

Orange

Green

Blue

Observed Frequency

33

26

21

8

7

5

Expected Frequency

30

20

20

10

10

10

H0: pbr = 0.3 and py = 0.2 and pr = 0.2 and po = 0.1 and pg = 0.1 and pbl = 0.1

H1: At least one of the above proportions is different from the claimed value.

Calculating the X2 Test Statistic for M&M Data

Color category

Observed frequency

Expected frequency

O - E

(O-E)2

(O-E)2

E

Brown

         

Yellow

         

Red

         

Orange

         

Green

         

Blue

         
           
 

100

100

X2 = E (O-E)2

E

What are the degrees of freedom?

What is the critical value for X2?

What is the test statistic for X2?

Is the null hypothesis rejected or accepted? Why?