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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 $620 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. 

Suppose you are interested in constructing a 95% confidence interval to determine the true proportion of residents in Kern County that are planning on voting for the republican candidate in the next presidential election. If you want to make sure that you are within 0.1 of the actual proportion, how many residents would you need to include in your sample? Reminder: It’s impossible to survey a fraction of a person

A study was conducted in 2018 comparing the average earnings (average annual salaries) of US citizens in each state. Suppose you are hired to provide a more recent comparison of the average salaries of US citizens by state. Specifically you are tasked to determine whether the average salary in California, Washington, and Oregon are identical. Assume that the annual salaries for each state are known to be normally distributed. The data table below shows the annual salaries of the 10 individuals from your survey from each state for this year.   Annual Salaries by State California Oregon Washington $78,080 $67,701 $79,966 $74,610 $64,404 $76,491 $76,127 $67,205 $79,674 $79,951 $67,377 $78,976 $78,808 $66,084 $80,517 $75,243 $67,490 $79,586 $78,191 $68,983 $77,306 $79,793 $68,775 $79,590 $74,424 $69,105 $80,506 $77,776 $65,160 $76,293   Carry out the appropriate hypothesis test at the

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 9 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.

A study was conducted to determine how movie lengths vary based on genre. As a part of that larger study, it was found that the average length of all movies is 117 minutes. Assume this data is normally distributed with a standard deviation of 26 minutes. Use this information to answer the following question.  What is the probability that a randomly selected movie is either shorter than 110 minutes or longer than 120 minutes? 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. 

Lebron James has made 50.4% of all of his shots throughout his career. If he were to play in a basketball game and attempt 37 shots, how many would he be expected to make? Make sure to round your answer to the nearest integer. 

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 180 local residents to gauge if they spent more time on social media or watching television. Out of the 180 residents who were surveyed, 96 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

A study was conducted to determine voter’s political party preferences in various cities in Kern County. The researchers conducting the study randomly sampled 100 individuals from these cities In the table below you can see the breakdown of how these individuals responded based on the city that they live in.  Political Party Preference by City Republican Democrat Other No Preference Bakersfield 43 34 8 15 Taft 52 20 10 18 Arvin 60 14 8 18   Use this information to carry out an appropriate test at the

Daniel was playing a board game with his family and he felt as if the die that they were using was an unfair die because it appeared as if some numbers were occurring more frequently than others, and he didn’t believe this was just due to random chance. Therefore, at the end of the game night, Daniel decided to roll the die 60 times and record the number of times that each number appeared. Those results are shown in the table below.  Dice Counts Number on Die 1 2 3 4 5 6 Count 8 14 8 8 14 8   Use this information to carry out an appropriate test at the

Kobe Bryant made 44.7% of all of his shots throughout his career. If he were to play in a basketball game and attempt 40 shots, how many would he be expected to make? Make sure to round your answer to the nearest integer.