-/ 1 Question 11 of 16 View Policies Current Attempt in Progress Transgender Adults A study' of transgender adults examines the age at which they began to transition and the age of their earliest memories of gender dysphoria. (In this exercise, we examine the age beginning transition and in Exercise 6.107 we examine the age of their earliest memories.) In the study of 210 transgender adults, the mean age at which they began transitioning was 32.6 with a standard deviation of 18.2. Find a 95% confidence interval for the mean age at which transgender adults begin transitioning. Zaliznyak M, Bresee C, and Garcia MM, "Age at First Experienceof Gender Dysphoria Among Transgender Adults Seeking Gender- Affirming Surgery," JAMA Network Open, March 16,2020. Some of the data has been approximated from informationin the paper. to Confidence interval (round to three decimal places): i e Textbook and Media Attempts: 0 of 6 used Submit Answer Save for Later

1. Most medical schools of require applicants for admission to take the Medical College Admissions Test (MCAT) examination. Scores on the MCAT are roughly normally distributed with a mean of 500 and a standard deviation of 10.6. 2. If a medical school will only admit students in the top 10%, what is lowest z-score the student can receive and still be admitted? (round to the nearest hundredth) 3. Most medical schools of require applicants for admission to take the Medical College Admissions Test (MCAT) examination. Scores on the MCAT are roughly normally distributed with a mean of 500 and a standard deviation of 10.6. What percentage of students score between 495 points and 520 points? (round to the nearest hundredth 4. Most medical schools of require applicants for admission to take the Medical College Admissions Test (MCAT) examination. Scores on the MCAT are roughly normally distributed with a mean of 500 and a standard deviation of 10.6. What percentage of students score…

12) A state fish hatchery raises trout for stocking streams and lakes. The size of the fish at release time can be controlled to a fair degree by varying the rate of feeding. The target is a mean of 10 ounces; if the fish are too small, those who catch the fish aren’t happy. A random sample of 75 fish were weighed at time of release and it was determined that the mean was 9.66 ounces with a standard deviation of 0.86 ounces. Test to determine if the fish being released have a population mean less than 10 ounces at the 0.01 significance level.

estioh 20 For a 4-unit class like Statistics, students should spend average of 12 hours studying for the class. A survey was done on 27 students, and the distribution of total study hours per week is bell-shaped with a mean of 14 hours and a standard deviation of 2.6 hours. Use the Empirical Rule to answer the following questions. a) 68% of the students spend between hours and hours on Statistics each week. b) 95% of the students spend between hours and hours on Statistics each week. c) 99.7% of the students spend between hours and hours on Statistics each week. Question Help: Written Example > Next Question DD 888 F9 80 FB F7 F6 F5 F4 F3 F2 F1 & 23 2$ 8. 9. 7 1 2 3 T Q W K H S F 8: < CO

10. In a study conducted to determine the role that sleep disorders play in academic performance, researcher Jane Gaultney conducted a survey of 503 randomly selected students with a known sleep disorder (such as narcolepsy, insomnia, or restless leg syndrome) and found their mean GPA was 2.65 with a standard deviation of 0.87. Similarly, she randomly selected 1342 students with no known sleep disorders, and found their mean GPA to be 2.82 with a standard deviation of 0.83. You may assume that both population GPA's are normally distributed. Use a significance level of 0.05 to test whether the two groups have different mean GPA's. As a follow-up, construct and interpret a 95% confidence interval for the true difference in the mean GPA's of the two groups. What would be the type I and type II errors for this problem?

Derby Leicester is a city planner preparing for a meeting with the mayor. He would like to show that the population mean age of the houses on Lincoln Street is less than the population mean age of the houses on Maple Street so that more resources are allotted to repair Maple Street. Derby uses information from a previous study to assume that the population standard deviation for the ages of the houses on Lincoln Street is 7.72 years and 8.39 years for the houses on Maple Street. Due to limited time, Derby randomly selects the houses on Lincoln Street and the houses on Maple Street from the city’s property records and then records the age of each house in years. The results of the samples are shown in the table below. Assuming the conditions needed for the hypothesis test have been met, what is the z test statistic for this hypothesis test, rounded to two decimal places? Lincoln Street Maple Street x¯¯¯1=50.91 years x¯¯¯2=59.27 years n1=41 n2=37

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9. The GRE is a test that is widely used by many Universities throughout the country to determine graduate (Masters, Doctorate, Professional, etc) admissions. It consists of three parts: Verbal Reasoning, Quantitative Reasoning, and Analytical Writing (Source: www.ets.org). The 2014-15 scores for the Analytical Writing portion of the GRE is approximately normal with a mean score u=3.5 and standard deviation o=0.9. Use the 68-95-99.7 rule to draw the distribution of the data. a) 68% of the Analytical Writing scores fall between and b) 95% of the Analytical Writing scores fall between and c) 99.7% of the Analytical Writing scores fall between and d) What percent of GRE Analytical Writing scores lie above 2.6? e) What percent of GRE Analytical Writing scores lie below 5.3? f) What percent of GRE Analytical Writing scores lie below 1.7? g) What percent of GRE Analytical Writing scores lie between 1.7 and 6.2? h) How much score do you need to be in the top 16%? i) How much score will push…

9. You are an agricultural consultant researching the effect of different ground surfaces for dairy cattle. On a particular farm, the cow stalls are covered with straw, and the farm produces an average of 750 gallons of milk per day. The farmer is interested in knowing whether he can increase his milk yield by swapping out the straw for cow waterbeds. After making the switch, the farmer measures his yield on 18 days, finding a sample mean of 810 gallons and a sample standard deviation of 80 gallons. a) Carry out a hypothesis test to ask whether the mean yield from cows on waterbeds is greater than the mean yield for cows on straw, using a = 0.01. Be sure to carry out all of the steps of a hypothesis test, and phrase your conclusion in a way that will be useful to the farmer.