8.60 M&Ms Does the maker of M&Ms(Mars, Inc.) use the same proportion of red candies in its plain and peanut varieties? A random sample of 56 plain M&Ms contained 12 red candies, and another random sample of 32 peanut M&Ms contained 8 red candies.

a. Construct a 95% confidence interval for the differ- ence in the proportions of red candies for the plain and peanut varieties.

b. Based on the confidence interval in part

a, can you conclude that there is a difference in the proportions of red candies for the plain and peanut varieties? Explain.