Premium Product Promotions, a market research firm, is trying to determine if there are differences in the brand of beer preferred by various customer groups.  Formulate and test a hypothesis for them using a = 0.05 if the following data are the preferences of a sample of 800. 

CUSTOMER GROUP                                              BRAND OF BEER

                                                                 Pale                      Golden                            Heavy

Housewives                                             75                           20                                     5

Businessmen                                           50                         130                                    20

Factory Workers                                       5                            25                                  170

College Students                                   100                          100                                 100