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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 74 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 local pizzeria delivers pizzas every day of the week and their delivery times are normally distributed with a mean of 30 minutes with a standard deviation of 4 minutes. Determine the interval that contains the middle 90% of delivery times. Explain how you arrived at your answer.    Hint: Try sketching the normal distribution defined above and using percentiles, and shade the desired region Make sure to type your interval in an interval format with your bounds rounded to 2 decimal places. For example, if you thought the lower bound was 50.123 and the upper bound was 60.123 then you would type (50.12, 60.12) as your interval. 

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 less than 86?   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.

The CBEST is a test that individuals in California must take before they can become substitute teachers at the K-12 level. One portion of the exam is devoted to mathematics and it consists of 50 multiple choice questions that each have 5 possible options. Suppose Jim took the CBEST test and decided to randomly guess on all 50 questions. Use this information to answer the following question.  What is the probability that Jim gets no less than 15 correct? 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.

Consider the following distribution of letter grades shown below for a calculus class. Create a bar graph of the data (making sure to order the data properly) and identify the shape of the distribution. Distribution Table of Letter Grades Letter Grade Count/Frequency A 4 B 4 C 4 D 4 F 4    

Construct a data set that consists of 5 values where the range is 10 and the mean is 15. Type your answer in the following format: {Value1, Value2, Value3, Value4, Value5}

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 112?   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 less than 103 or greater than 89?   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 less than 112 and greater than 115?   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.

Suppose you are hired to determine the true average amount of money that college students make while working on-campus jobs. If you want to be 95% confident that you are within $80 of the actual value, how many students would you need to survey? Assume that the true standard deviation is $600.  Reminder: It’s impossible to survey a fraction of a college student.