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Suppose you are carrying out a 1-sample t-test and your given sample size is 35. What would be the corresponding degrees of freedom?

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 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.

IQ scores are normally distributed with a mean of 100 and a standard deviation of 15. Use this information to answer the following question. What is the probability that a randomly selected person will have an IQ score of at most 97? 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.

Select the statistical term that most closely matches the definition below: “The collection of all objects of interest in a statistical study”

IQ scores are normally distributed with a mean of 100 and a standard deviation of 15. Use this information to answer the following question. What is the probability that a randomly selected person will have an IQ score of at least 120? 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.

Which type of sampling process is not considered a valid random sample?

State all of the assumptions that are required for carrying out a goodness of fit test as well as how you would check those assumptions. Be as specific as possible. 

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 at most 9 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 sample data set below. Calculate the median.  {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

State all of the assumptions that are required for carrying out a 2-sample z-test for difference in proportions as well as how you would check those assumptions. Be as specific as possible.