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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 26 students in his class and their final letter grades are shown below.  Distribution Table of Letter Grades Letter Grade Count/Frequency A 4 B Left Blank on Purpose C 10 D 3 F 1 Total 26 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 carried out by a gaming company to try and determine the true proportion of teenagers that were interested in an upcoming video game they were releasing. The company decided to randomly survey 500 teenagers and they found that 184 of them were planning on purchasing the game when it comes out. Use this information to construct and interpret a 94% confidence interval for the true proportion of teenagers who plan to purchase the video game when it comes out. 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 study was conducted where the heights of students in middle schools from around the county  were collected and analyzed. The data was normally distributed and they found that the mean height of those middle school students was 1.512 meters with a standard deviation of 0.07 meters.  Calculate the corresponding z-score for a student whose height was 1.55 meters tall.    Make sure to round your final answer to 3 decimal places. For example, if you thought the answer was 1.462178 then you would type in 1.462.

A local landscaping company was running a promotional offer to plant drought resistant trees for homeowners, and the survival rate for those plants has been 91% in the past. Christine just bought a new home and she is looking to hire the company to plant 10 drought resistant trees in her yard. What is the probability that at most 6 of those trees survive? Make sure to type in your answer rounded to 2 decimal places. For example, if you thought the answer was 1.23456, then you would type in 1.23.

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 shorter than 76 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. 

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 more than 78 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. 

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 most 71 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. 

According to the Bureau of Labor Statistics, in 2019 U.S. households spent an average of $386.92 per month on food. Assume this data is normally distributed with a standard deviation of $112. Use this information to answer the following question.  What Z-score would correspond to a household that spent an average of $400 on food per month in 2019? Make sure to round your answer to 2 decimal places; i.e. if your answer was 87.654321 then you would type in 87.65. 

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 12 to 23 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 landscaping company was running a promotional offer to plant drought resistant trees for homeowners, and the survival rate for those plants has been 91% in the past. Christine just bought a new home and she is looking to hire the company to plant 10 drought resistant trees in her yard. What is the probability that at least 7 of those trees survive? Make sure to type in your answer rounded to 2 decimal places. For example, if you thought the answer was 1.23456, then you would type in 1.23.