(d)
Explain to someone who knows no statistics but is interested in weight-loss programs what the
practical conclusion is.
Chapter 12
3
Test 12A

10.
Mars Inc., makers of M&M’s candies, claims that they produce plain M&M’s with the following
distribution:
Brown:
30%
Red:
20%
Yellow:
20%
Orange: 10%
Green:
10%
Blue:
10%
A bag of plain M&M’s was selected randomly from the grocery store shelf, and the color counts
were as follows:
Brown:
16
Red:
11
Yellow:
19
Orange:
5
Green:
7
Blue:
3
(a)
You want to conduct an appropriate test of the manufacturer’s claim for the proportion of
yellow M&M’s.
Identify the population and parameter of interest.
Then state hypotheses.
(b) State and verify the conditions for performing the significance test.
(c) Calculate the test statistic and the
P
-value.
(d) What do you conclude about the manufacturer’s claim?
Explain.
(e)
Based on this sample, construct and interpret a 90% confidence interval for the proportion of
yellow M&M’s candies produced by Mars.
Chapter 12
4
Test 12A