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A tech company was planning on conducting a survey of its employees to gauge how many devices they use on average during a typical day. Those individuals in charge of the study want to ensure they were within 2 of the true mean value with 95% confidence. How large of a sample would they need to take if the true standard deviation for this data was 9.1. Make sure to round your answer properly since it is impossible to survey a fraction of a person. 

A study was conducted of college students that stated the true average number of units that a college student enrolls in each semester is 12.7 with a true standard deviation of 6.8. Suppose you randomly sampled 40 college students and recorded the number of units that each of them were enrolled in. Use this information to answer the following question.  What is the probability that the average number of units those students from your sample were enrolled in was less than 13.4.? Make sure to round your answer to 2 decimal places; i.e. if your answer was 0.54321 then you would type in 0.54. 

A study was conducted of college students that stated the true average number of units that a college student enrolls in each semester is 12.7 with a true standard deviation of 6.8. Suppose you randomly sampled 40 college students and recorded the number of units that each of them were enrolled in. Use this information to answer the following question.  What is the probability that the average number of units those students from your sample were enrolled in was more than 12.9.? Make sure to round your answer to 2 decimal places; i.e. if your answer was 0.54321 then you would type in 0.54. 

The CEO of a major tech company was interested in developing a new type of tablet. However, before she decided how much money she wanted to invest in research and development, she wanted to conduct a survey to determine the average amount of time a person spends on their tablet each day. She had her employees conduct a survey of 1000 randomly selected individuals who owned tablets. As part of the survey, they found that those 1000 individuals spent an average of 1.17 hours per day on their tablets. Assume the true standard deviation amount of time that someone spends on their tablet per day is 2.45 hours. Use this information to construct and interpret a 92% confidence interval for the true average amount of time a person spends on their tablet each day.  Make sure that you are addressing the following in your response.  Check any and all relevant assumptions and state specifically how they are/aren’t satisfied State the desired confidence interval (round any values in your interval to 2 decimal places, i.e. 54.321 would be rounded to 54.32) Interpret the interval in context of the scenario provided. 

A professor at a local community college decided to try out a new lecture format for his statistics class, and he was curious how well students performed using this new format. So the professor decided to record every student’s final grade at the end of the semester to determine how effective this new lecture format was. There were 33 students in his class and their final letter grades are shown below.  Distribution Table of Letter Grades Letter Grade Count/Frequency A 6 B Left Blank on Purpose C 11 D 4 F 3 Total 33 What percentage (relative frequency) of students received a B? Give your answer as a percentage rounded to 2 decimal places (i.e. If the answer is 17.43%, simply type in 17.43)

A study was conducted that found 15% of all US adults have some form of student loan debt. Suppose you were to randomly sample 100 US adults. What is the probability that at anywhere from 10 to 20 of them would have student loan debt? Use a binomial distribution to answer this question. Make sure to round your answer to 2 decimal places; i.e. if your answer was 0.654321 then you would type 0.65

A local restaurant was trying to figure out the best way to advertise to attract new customers from this town. The owner had a set amount of money to spend on advertising and they were trying to figure out if it was better to invest in advertisements on social media or television commercials. They conducted a survey of 600 local residents to gauge if they spent more time on social media or watching television. Out of the 600 residents who were surveyed, 312 of them stated that they spent more time on social media than watching television.  Use this information to carry out the appropriate hypothesis test at the

The average height for an NCAA Division 1 men’s basketball player is 77 inches. Assume this data is normally distributed with a standard deviation of 8 inches. Use this information to answer the following question.  What is the probability that a randomly selected NCAA D1 men’s basketball player is at least 80 inches tall? Make sure to round your answer to 2 decimal places; i.e. if your answer was 0.654321 then you would type in 0.65. 

A recent study was conducted and it found that IQ’s are normally distributed with a mean of 100 and a standard deviation of 15. Use this information to find the following probability.  What is the probability that a randomly selected individual would have an IQ between 82 and 106?   Make sure to write your answer as a decimal rounded to 3 decimal places. For example, if you thought the answer was 23.173% then you would type in 0.232.

A business professor was interested in seeing how students had fared on her final exam over the years. She looked back at students who had taken her class over the last 5 years and recorded their exam scores and summarized that information in the table below. Suppose you were to construct a histogram based on this data (starting with 0-9 group on the far left) identify what the overall shape of the data would look like.  Final Exam Breakdown Final Exam Score Frequency 0 – 9 1 10 – 19 2 20 – 29 0 30 – 39 1 40 – 49 6 50 – 59 8 60 – 69 10 70 – 79 29 80 – 89 30 90 – 100 34