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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 63rd 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 study was conducted and it found that the mean annual salary for all California residents was $63,783 and the true standard deviation for all California residents was $7,240. Suppose you were to randomly sample 50 California residents. Use this information to answer the following question.  What is the probability that the average salary for the 50 individuals in your sample would be anywhere from $64,000 to $67,000? Make sure to type in your answer as a decimal rounded to 3 decimal places. For example, if you thought the answer was 0.54321 then you would type in 0.543.

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 83rd 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.

Consider the following sample data set below. Calculate the mean.  {12, 18, 6, 7, 8, 14, 21, 15, 3, 17} Make sure to round your final answer to 2 decimal places. For example, if you thought the final answer was 87.6543 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 least 108?   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 probability.  What is the probability that a randomly selected individual would have an IQ between 105 and 119?   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.

Isabella works for an insurance company and she is the director of the customer service department. One of her main goals is to reduce the wait times that customers experience when they call the department before they are connected to someone that can help them. She recorded all of the wait times that customers experienced in a given month and recorded it in the frequency distribution table below.  Suppose you were to construct a histogram based on this data (starting with the 0-5 minute group on the far left) identify what the overall shape of the data would look like.  Customer Wait Time Breakdown Minutes Spent Waiting Frequency 0 – 5 67 6-10 34 11-15 14 16-20 5 21-25 1 26+ 0  

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 75 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. 

Suppose a study was conducted of community colleges in California to determine the average cost of tuition for in-state students. The study consisted of 45 community colleges from California. Based on the sample data, the average tuition was $1,420 and the sample standard deviation was $262. Use this information to construct and interpret a 92% confidence interval for the true average tuition of all California community colleges.    Make sure to address the following in your response: Check any and all relevant assumptions and state how you determined whether or not they were satisfied (Be as specific as possible) Make sure to type your confidence interval in an interval format with each bound rounded to the nearest whole number.  Make sure to include an interpretation in context of the given problem  

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 0.18 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