In 2003, Computers of Brand a Controlled 25% of the Market

Essay

In 2003, computers of Brand A controlled 25% of the market, Brand B 20%, Brand C 10% and Brand D 45%. In 2004, sample data were collected from many randomly selected stores throughout the country. Of the 1200 computers sold, 280 were Brand A, 270 were Brand B, 90 were Brand C and 560 were Brand
D.Has the market changed since 2003? Test at the 1% significance level.