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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 $370 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 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 of at most 118?   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 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 1.4 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 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 25 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; i.e. if your answer was 0.654321 then you would type 0.65

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 0 20 – 29 2 30 – 39 3 40 – 49 2 50 – 59 10 60 – 69 20 70 – 79 47 80 – 89 55 90 – 100 58  

In 2018, a study was conducted that stated 22.6% of residents in Kern County live below the poverty line. Suppose you were hired to determine if that percentage has changed since the study was conducted. You randomly sample 200 residents from Kern County and find that 41 of them fall below the poverty line. Carry out the appropriate hypothesis test at the

In 2018, a study was conducted that stated 22.6% of residents in Kern County live below the poverty line. Suppose you were hired to determine if that percentage has changed since the study was conducted. You randomly sample 200 residents from Kern County and find that 37 of them fall below the poverty line. Carry out the appropriate hypothesis test at the

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 of more than 94?   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 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 value below.  What IQ score would represent the 73rd percentile?   Make sure to write your answer as a decimal rounded to 3 decimal places. For example, if you thought the answer was 123.4567 then you would type in 123.457.

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 28 students in his class and their final letter grades are shown below.  Distribution Table of Letter Grades Letter Grade Count/Frequency A Left Blank on Purpose B 6 C 11 D 4 F 1 Total 28 What percentage (relative frequency) of students received an A? Give your answer as a percentage rounded to 2 decimal places (i.e. If the answer is 17.43%, simply type in 17.43)