In 2006, the VISA network wanted to move away from its long-standing television advertising theme that stated 'Visa is everywhere you want to be.' ...

In 2006, the VISA network wanted to move away from its long-standing television advertising theme that stated 'Visa is everywhere you want to be.' During the Winter Olympics, the Visa network offered athletes commercials with a broader message, including insurance, withdrawal cards, and payment technologies such as remote processing. One of the first commercials featured skier Lindsey Jacobellis being calmed down, before an important race, by imagining that her Visa withdrawal card had been stolen. A key indicator for the success of television advertising is the proportion of viewers who 'really like the commercials.' The Harris Ad Research Service conducted a study of 903 adults who watched the new Visa commercial and reported that 54 of them really liked the commercials. According to Harris, the proportion of a typical television advertisement that receives a 'really like the commercials' rating is 0.21. a) Use the critical value approach for the hypothesis test and a significance level of 0.05 to try to prove that the new Visa commercial is less successful than a typical commercial. b) Use the p-value approach and a significance level of 0.05 to try to prove that the new Visa commercial is less successful than a typical commercial.