csat-suneung 2008 Q30

csat-suneung · South-Korea · csat__math-science 4 marks Confidence intervals Find a specific bound or margin of error from the CI formula
(Probability and Statistics) To determine the proportion $p$ of students arriving before 8 AM at a certain high school, 300 students were randomly sampled from the school on a certain day, and the sample proportion $\hat{p}$ of students arriving before 8 AM was obtained. Using the sample proportion $\hat{p}$, the 95\% confidence interval for the proportion $p$ is $[ 0.701, 0.799 ]$. Find the number of students among the 300 randomly sampled students who arrived before 8 AM. (Note: When $Z$ follows the standard normal distribution, $\mathrm { P } ( | Z | \leqq 1.96 ) = 0.95$.) [4 points]
(Probability and Statistics) To determine the proportion $p$ of students arriving before 8 AM at a certain high school, 300 students were randomly sampled from the school on a certain day, and the sample proportion $\hat{p}$ of students arriving before 8 AM was obtained. Using the sample proportion $\hat{p}$, the 95\% confidence interval for the proportion $p$ is $[ 0.701, 0.799 ]$. Find the number of students among the 300 randomly sampled students who arrived before 8 AM. (Note: When $Z$ follows the standard normal distribution, $\mathrm { P } ( | Z | \leqq 1.96 ) = 0.95$.) [4 points]