4, The verbal part of the Graduate Record Exam (GRE) has a mean (u) of 500 and a standard deviation (ơ) of 100. Use the normal distribution to answer the following questions: a. If we wanted to select only students at or above the 90th percentile, what verbal GRE score would we use as a cutoff? b. What verbal GRE score corresponds to a percentile rank of 15%? 55%? C. What is the percentile rank of a verbal GRE score of 628? 350? d. If we randomly selected 1,500 students who had taken the verbal GRE, how many would we expect to score lower than 250? Higher than 750?

Please answer the following three multiple choice questions :) Summarized below are data for a study to see if hours of sleep per day for med and non-med students are the same:   n     x¯ s med students 25 5.8 0.83 non-med students 32 6.3 1.39 1. Find the test statistic (assume unequal standard deviation) A. -15.44 B. -5.69 C. -1.69 D. -1.81 2. Let tstat represent the value of the test statistic from the previous question. The degrees of freedom for the test are df = 52. To test the claim that the mean hours of sleep for med and non-med students is different, the P-value is calculated as: A. 2*pt( tstat, df=52, lower.tail = TRUE) B. 2*pt( tstat, df=52, lower.tail = FALSE) C. pt( tstat, df=52, lower.tail = TRUE) D. pt( tstat, df=52, lower.tail = FALSE) 3. The correct P-value is 0.098. At α = 0.05, we A. reject H0. The claim that means are different is not supported. B. reject H0. The claim that means are different is supported. C. fail to reject…

A successful basketball player has a height of 6 feet 11 ​inches, or 211 cm. Based on statistics from a data​ set, his height converts to the z score of 5.17. How many standard deviations is his height above the​ mean?

The weights for newborn babies is approximately normally distributed with a mean of 6.1 pounds and a standard deviation of 1.8 pounds. Use the Cumulative Z-Score Table to answer the questions below. Write your answers rounded to the nearest whole number. Consider a group of 1200 newborn babies: • How many would you expect to weigh between 7.72 and 9.34 pounds? • How many would you expect to weigh less than 9.7 pounds? How many would you expect to weigh more than 6.37 pounds? How many would you expect to weigh between 6.1 and 7.54 pounds?

The Mathematics section of the ACT test had a mean of 20.9 and an SD of 5.3 for the years 2013–2015. Suppose these are well modeled by a Normal distribution. ​a) About what percent of students scored over 33? ​b) About what percent of students scored under 16? ​c) About what percent of students scored between 16 and 33?

Given the following grades on s test: 86, 92, 100, 93, 89, 95, 79, 98, 68, 62, 71, 75, 88, 86, 93, 81, 100, 86, 96, 52; What is the percentage of scores lying within one standard deviation from the mean? Two standard deviations from the mean? Are these results consistent with what