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Essay Question #1 Make sure your answer to the following Z-prop significance test is written on paper and submitted to the final exam upload and score module before you leave Zoom. According to a 2017 survey, Millennial males in the US were more likely to own a cat then their female counterparts. 48% of the male Millennial survey respondents stated that they owned a cat, compared to 35% of the females who responded. Suppose a SRS survey of 255 Millennial females was conducted last year and found that 99 said they were cat owners. Using a significance level of 0.05, is there significant evidence to claim that the proportion of female Millennial cat owners in the US is different than 35%? Be sure to include the following: 1. State an appropriate null and alternative hypotheses. 2. Find a test statistic. Show all your work- formula used and answer. 3. Find the P-value. 4. Make a conclusion. 5. Write one to two sentences explaining what your test found in the context of the problem using non statistical language. 

Essay Question #2 Make sure your answer to the following two-sample confidence interval is written on paper and submitted to the final exam upload and score module before you leave Zoom. The PLNU is trying to determine if basketball players weigh more that baseball players.  A random sample was taken of 47 basketball players and their mean weight was 192 lbs with a standard deviation of 21.4 lbs.  A random sample of 54 baseball players was taken and their mean weight was 187 lbs with a standard deviation of 19.1 lbs.  Give a 95% confidence interval for the mean difference in the average weights of PLNU basketball and baseball players. Be sure to show all formulas, work, and numbers used (e.g. & critical value).  At the end of your work, write a one or two sentence summary in non-statistical language to describe what you have found, not how you found it.

Glenda is trying to test the ball bearings from her new factory. She knows the machines should produce a ball bearing with weight 2.730 grams and a standard deviation of 0.18 grams. What size simple random sample should she plan to take to be 90% sure the true mean of the new bearings are off in weight by no more than 0.02 grams? The correct number is in the range:

Essay Question #1 Make sure your answer to the following Z-prop significance test is written on paper and submitted to the final exam upload and score module before you leave Zoom. According to a 2017 survey, Millennial males in the US were more likely to own a cat then their female counterparts. 48% of the male Millennial survey respondents stated that they owned a cat, compared to 35% of the females who responded. Suppose a SRS survey of 255 Millennial males was conducted last year and found that 151 said they were cat owners. Using a significance level of 0.05, is there significant evidence to claim that the proportion of male Millennial cat owners in the US is different than 48%? Be sure to include the following: 1. State an appropriate null and alternative hypotheses. 2. Find a test statistic. Show all your work- formula used and answer. 3. Find the P-value. 4. Make a conclusion. 5. Write one to two sentences explaining what your test found in the context of the problem using non statistical language. 

Essay Question #3 Make sure your answer to the following two-sample confidence interval is written on paper and submitted to the final exam upload and score module before you leave Zoom. From the stemplot given below, find the following items: 1. Min 2. Max 3. Q1 4. Q3 5. Median 6. Mean 7. Comment on the shape – i.e. symmetry or skewed (which way?) and state why you think this.

Essay Question #2 Make sure your answer to the following two-sample confidence interval is written on paper and submitted to the final exam upload and score module before you leave Zoom. The PLNU is trying to determine if basketball players weigh more that baseball players.  A random sample was taken of 47 basketball players and their mean weight was 192 lbs with a standard deviation of 23.4 lbs.  A random sample of 54 baseball players was taken and their mean weight was 187 lbs with a standard deviation of 17.1 lbs.  Give a 90% confidence interval for the mean difference in the average weights of PLNU basketball and baseball players. Be sure to show all formulas, work, and numbers used (e.g. & critical value).  At the end of your work, write a one or two sentence summary in non-statistical language to describe what you have found, not how you found it.  

Essay Question #4 Make sure your answer to the following T-test is written on paper and submitted to the final exam upload and score module before you leave Zoom. A researcher reads a paper introducing a new test of executive function. The authors of the paper had tested healthy volunteers and found that on average they score 71 on the new test. The researcher believes that patients with schizophrenia will score less than the normal average on this test of executive function. They test 21 patients with schizophrenia. The average score for the patients is 66 with a standard deviation of 8.2. Is there significant evidence at the 5% significance level to support the researcher’s claim? Be sure to include the following: 1. State an appropriate null and alternative hypotheses. 2. Find a test statistic. Show all your work- formula used and answer. 3. Find the P-value. 4. Make a conclusion. 5. Write one to two sentences explaining what your test found in the context of the problem using non statistical language. 

Glenda is trying to test the ball bearings from her new factory. She knows the machines should produce a ball bearing with weight 2.730 grams and a standard deviation of 0.23 grams. What size simple random sample should she plan to take to be 99% sure the true mean of the new bearings are off in weight by no more than 0.02 grams? The correct number is in the range:

If we take samples from normal populations and construct two confidence intervals (CI) for which the only difference is that one of them was at the 80% confidence level and the other was at the 90% level, which of the following statements

Administrators wonder how much time students spend at the beach each week.  They report the 85% confidence interval as 65