Several years ago the proportion of Americans aged 18 - 24 who invested in the stock market was 0.20. A random sample of 25 Americans in this age group was recently taken. They were asked whether or not they invested in the stock market. The results follow:

	yes	no	no	yes	no
	no	yes	no	no	yes
	no	no	no	no	no
	no	no	no	yes	no
	no	no	yes	no	no

At a .05 level of significance, set up a hypothesis test to determine whether or not the proportion of Americans 18 - 24 years old that invest in the stock market has changed.