In Los Angeles there are three network television stations, each with it own evening ...

     In Los   Angeles there are three network television stations, each with it own evening   news program from 6:00 to 6:30 PM. According to a report in this morning’s   local newspaper, a random sample of 150 viewers last night revealed 53   watched the news on KNBC (channel 2), 64 watched KABC (channel 7), and 33   viewed KCBS (channel 2). At the 0.05 significance level, is there a   difference in the proportion of viewers watching the three channels?