At a large university, 68% of the students have a laptop, while only 43% of professors have one. Let Ps and pp be the sample proportions of students and professors, respectively, who have a laptop. Suppose 56 students and 31
professors from this university are selected at random and asked if they have a laptop.
Which of the following is the correct calculation and interpretation of the standard deviation of the sampling
distribution of ps-p?
The difference (student - professor) in the sample proportions of those who have a laptop typically varies about
0.012 from the true difference in proportions.
The difference (student - professor) in the sample proportions of those who have a laptop typically varies about
0.035 from the true difference in proportions.
The difference (student - professor) in the sample proportions of those who have a laptop typically varies about
0.109 from the true difference in proportions.
The difference (student - professor) in the sample proportions of those who have a laptop typically varies about
0.25 from the true difference in proportions.