The registrar of a large university knows that 23 % of the students come to coll
ID: 2959596 • Letter: T
Question
The registrar of a large university knows that 23% of the students come to college with credit for an advance placement (AP) course. The registrar is going to conduct interviews with 100 students regarding their experiences at the university. Depending on which students are chosen, the proportion of students in the sample that have AP credit may vary.
Note: Report your answers to 3 decimal places.
If you are having difficulties with this question, you may want to review pages 369-370 in Mind on Statistics.
In a sample of 200 students what is the probability that over 27% of the sample had AP credit? 3
Explanation / Answer
In a sample of 100 students, what is the probability that over 27% of the sample has AP credit?
P(p>0.27) = P((p-0.23)/[0.23*(1-0.23)/100] > (0.27-0.23)/sqrt(0.23*(1-0.23)/100))
=P(Z>0.95)
= 0.1711 (check standard normal table)
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In a sample of 200 students what is the probability that over 27% of the sample had AP credit?
P(p>0.27) = P((p-0.23)/[0.23*(1-0.23)/200] > (0.27-0.23)/sqrt(0.23*(1-0.23)/200))
=P(Z>1.34)
= 0.0901 (check standard normal table)