Since the first release of Superman in 1978, stories of superheroes have dominated blockbuster movies. Their unprecedented physical prowess and dedication to humanity draw a wide range of audience. In the last decade, there have been many successful superhero movies including Superman, Spiderman, X-men, Batman, Blade, Watchmen, Iron man, and Thor. Before the upcoming release of the movie, The Men of Steel, a reporter from BusinessWeek wants to know what percentage of undergrad students think that Superman is their favorite superhero. A random sample of 63 people shows that 6 students choose Superman as their favorite superhero.

Required:
Construct a 90% confidence interval for the true proportion of undergrad students whose favorite superhero is Superman.