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A study was conducted that found 46.9% of all smartphone users in the US had an iPhone. Suppose you were to randomly sample 40 US smartphone users.   What is the probability that at most 14 of them had an iPhone? Use a binomial distribution to answer this question. Make sure to round your answer to 2 decimal places (For example, if your answer was 0.654321 then you would type 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 $320 on food per month in 2019?  Make sure to round your answer to 2 decimal places. For example, if your answer was 87.654321 then you would type in 87.65. 

A study was conducted in 2018 to look at average annual salaries for individuals who lived in Wisconsin. It found that on average individuals in Wisconsin earned $56,302 per year. Assume the true standard deviation for annual salary was $8,000. Suppose you took a random sample of 50 individuals from Wisconsin in 2018 and recorded their salaries. Use this information to answer the following question.   What is the probability that the average salary for those 50 individuals in your sample would fall between $57,000 and $62,000 per year?  Make sure to round your answer to 2 decimal places. For example, if your answer was 0.654321 then you would type 0.65

A study was conducted that found 83% of all teenagers in the US own at least one video game console. Suppose you were to randomly sample 30 US teenagers.   What is the probability that exactly 24 of them would own at least one video game console? Use a binomial distribution to answer this question. Make sure to round your answer to 2 decimal places (For example, if your answer was 0.654321 then you would type 0.65)

A study was conducted that found 46.9% of all smartphone users in the US had an iPhone. Suppose you were to randomly sample 40 US smartphone users.   What is the probability that at most 18 of them had an iPhone? Use a binomial distribution to answer this question. Make sure to round your answer to 2 decimal places (For example, if your answer was 0.654321 then you would type 0.65)

Consider a town where the average age of all individuals is 34.3 years old with a standard deviation of 14.7 years. Suppose you were to randomly select 50 individuals from this town as part of a study.    What is the probability that the average age of the 50 individuals in your study would be less than 40 years old and greater than 50 years old? Make sure to round your answer to 2 decimal places. For example, if your answer was 0.654321 then you would type 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 shorter than 76 inches tall?  Make sure to round your answer to 2 decimal places (For example, if your answer was 0.654321 then you would type 0.65)

Consider a town where the average age of all individuals is 34.5 years old with a standard deviation of 12.2 years. Suppose you were to randomly select 50 individuals from this town as part of a study.    What is the probability that the average age of the 50 individuals in your study would be less than 38 years old or greater than 36 years old? Make sure to round your answer to 2 decimal places. For example, if your answer was 0.654321 then you would type 0.65

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 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. For example, if your answer was 0.654321 then you would type 0.65