13. M&M’S Does Mars, Inc. use the same proportion of red M&M’S in its plain and peanut varieties? Random samples of plain and peanut M&M’S provide the following sample data:

a. Use a test of hypothesis to determine whether there is a significant difference in the proportions of red candies for the two types of M&M’S. Let a 5.05.

b. Calculate a 95% confidence interval for the difference in the proportion of red candies for the two types of M&M’S. Does this interval confirm your results in part a?

Plain Peanut Sample Size 56 32 Number of Red M&M'S 12 8