A recent report estimated that 25% of all college students in the United States have a sexually transmitted disease (STD). Due to the demographics of the community, the director of the campus health center believes that the proportion of students who have a STD is lower at his college. He tests H0: p = 0.25 versus Ha: p < 0.25.
The campus health center staff select a random sample of 50 students and determine that 18% have been diagnosed with a STD.
a) Is the sample size condition for conducting a hypothesis test for a population proportion satisfied?