In a large high school, 18% of sophomores and 67% of seniors have part-time jobs. Suppose random samples of 32 sophomores and 31 seniors from this uigh school are asked if they have a part-time job. Let under and Pupper be the
sample proportions of sophomores and seniors, respectively, who have part-time jobs.
Which of the following is the correct shape and justification of the sampling distribution of Punder - Pupper?
O bimodal because one population proportion is centered at 0.18, while the other is centered at 0.67
O approximately Normal because the expected numbers of successes and failures for each sample are all at least 10
O not approximately Normal because the expected numbers of successes and failures for each sample are all at least
10
O not approximately Normal because the expected numbers of successes and failures for the sophomores group are
not both at least 10