An alumni association wants to estimate the mean debt of this year's college graduates. It is known that the population standard deviation of the debts of this year's college graduates is $11.800. How large a sample should be selected so that the estimate with a 99% confidence level is within $800 of the population mean?

Loretta, who turns eighty this year, has just learned about blood pressure problems in the elderly and is interested in how her blood pressure compares to those of her peers. Specifically, she is interested in her systolic blood pressure, which can be problematic among the elderly. She has uncovered an article in a scientific journal that reports that the mean systolic blood pressure measurement for women over seventy-five is 134.1mmHg, with a standard deviation of 5.9 mmHg. Assume that the article reported correct information. Complete the following statements about the distribution of systolic blood pressure measurements for women over seventy-five. (a)According to Chebyshev's theorem, at least ________% of the measurements lie between 122.3 mmHg and 145.9 mmHg. (b)According to Chebyshev's theorem, at least 56% of the measurements lie between __________ mmHg and mmHg. (Round your answer to 1 decimal place.)

It is known that average house prices today is $371,040 higher compared to 10 years ago and median in the current time also $382,000 higher than house prices 10 years ago. Provide an interpretation of the change of mean and median based on the information above. Compare and contrast these values and comment on the distribution of the increases in house prices.

A researcher would like to estimate the mean amount of money that a family spends to within $75. If the amount spent by a family is considered to be normally distributed with a standard deviation of $412, what sample size would be necessary to be 93% confident?

The average wage for bank managers in a certain city is $91,900 per hour with a standard deviation of $24,300. What should be the hourly wage for an administrator if he/she wishes to earn less than 25% of all employees?

A psychologist is studying the self image of smokers, as measured by the self-image (SI) score from a personality inventory. She would like to examine the mean SI score, μ, for the population of all smokers. Previously published studies have indicated that the mean SI score for the population of all smokers is 82and that the standard deviation is 12, but the psychologist believes that the value for the mean has decreased. She plans to perform a statistical test. She takes a random sample of SI scores for smokers and computes the sample mean to be 7.Based on this information, answer the questions below. What are the null hypothesis (H0) and the alternative hypothesis (H1) that should be used for the test?H0: μ is ?less than less than or equal togreater thangreater than or equal to not equal toequal to ? 82 74 12 H1: μ is ?less thanless than or equal togreater thangreater than or equal tonot equal toequal to ? 82 74 12 In the context of this test, what is a Type II error?A Type…

Loretta, who turns eighty this year, has just learned about blood pressure problems in the elderly and is interested in how her blood pressure compares to those of her peers. Specifically, she is interested in her systolic blood pressure, which can be problematic among the elderly. She has uncovered an article in a scientific journal that reports that the mean systolic blood pressure measurement for women over seventy-five is 132.6 mmHg , with a standard deviation of 6.9 mmHg .   Assume that the article reported correct information. Complete the following statements about the distribution of systolic blood pressure measurements for women over seventy-five. (a)According to Chebyshev's theorem, at least 56% of the measurements lie between mmHgandmmHg. (Round your answer to 1 decimal place.) (b)According to Chebyshev's theorem, at least ▼(Choose one) of the measurements lie between 118.8 mmHg and 146.4 mmHg .

A psychologist is studying the self image of smokers, as measured by the self-image (SI) score from a personality inventory. She would like to examine the mean SI score,  μ , for the population of all smokers. Previously published studies have indicated that the mean SI score for the population of all smokers is  80  and that the standard deviation is  12 , but the psychologist believes that the value for the mean has decreased. She plans to perform a statistical test. She takes a random sample of SI scores for smokers and computes the sample mean to be  74 . Based on this information, answer the questions below. What are the null hypothesis ( H0 ) and the alternative hypothesis ( H1 ) that should be used for the test? H0 :  μ  is ?less thanless than or equal togreater thangreater than or equal tonot equal toequal to ?748012 H1 :  μ  is ?less thanless than or equal togreater thangreater than or equal tonot equal toequal to ?748012In the…

Loretta, who turns 91 this year, has heard that the mean systolic blood pressure among the elderly is 120 millimeters of mercury (mm Hg), but she believes that the actual value is higher. She bases her belief on a recently reported study of 19 randomly selected, elderly adults. The sample mean systolic blood pressure of the adults in the study was 121 mm Hg , and the sample standard deviation was 20 mm Hg. Assume that the population of systolic blood pressures of elderly adults is normally distributed. Based on the study, at the 0.1 level of significance, can it be concluded that μ , the mean systolic blood pressure among elderly adults, is greater than 120 mm Hg? Perform a one-tailed test. Then complete the parts below. Carry your intermediate computations to three or more decimal places and round your answers as specified in the table. (a) State the null hypothesis H0? and the alternative hypothesis H1? . H0:? H1:? (b) Determine the type of test statistic to…

An alumni association wants to estimate the mean debt of this year's college graduates. It is known that the population standard deviation of the debts of this year's college graduates is $11,800. How large a sample should be selected so that the estimate with a 99% confidence level is within $800 of the population mean?