An electronic survey of 7061 players of Guitar Hero and Rock

An electronic survey of 7,061 players of Guitar Hero and Rock Band reported that a 67% of those who do not currently play a musical instrument said that they are likely to begin playing a real musical instrument in the next two years. The reports describing the survey do not give the number of respondents who do not currently play a musical instrument.

Give a 99% confidence interval for the population proportion who would say that they are likely to being playing a real instrument in the next two years if only 25% of the respondents said that they did not currently play a musical instrument?

Solution