Suppose that 14% of the students at a university have a full- time job. If a random sample is to be selected from the students at this university, what is the smallest sample size for which it would be reasonable to think the sampling distribution of p?, the proportion in the sample who have full-time jobs, would be approximately normal? (A) 10 students (B) 11 students (C) 12 students (D) 71 students (E) 72 students A population has a proportion of successes of 0.2. Let p? be the proportion of successes in a random sample from this population. How large would n have to be in order for the standard deviation of p? to be less than 0.01? (A) 16 (B) 64 (C) 256 (D) 1600 (E) 4000
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