Question

Beview 1JA survey of 700 non-fatal accidents showed that 183 involved faulty equipment. Find a point estimate for p, the population proportion of accidents that involved faulty equipment. 2) An article a Florida newspaper reported on the topics that teenagers most want to discuss with their pare nts. The findings, the results of a poll, showed that 46% would like more discussion about the family's financial situation, 37% would like to talk about school, and 30% would like to talk about religion. These and other percentages were based on an proportion of all teenagers who want more family discussions about school. Use a 98% confidence level Interpret the result ational sampling of 521 teenagers. Estimate the P 3JA researcher at a major clinic wishes to estimate the proportion of the adult population of the United States that has sleep deprivation. How large a sample is needed in order to be 98% confident that the sample proportion will not differ from the true proportion by more than 5%? 4)A random sample of 10 parking meters in a resort community showed the following incomes for a day Assume the incomes are normally distributed. Find the 95% confidence interval for the true mean. Round to the nearest cent. $3.60 $4.50 $2.80 $6.30 $2.60 $5.20 $6.75 $4.25 $8.00 $3.00 5)Determine the sample size required to estimate the mean score on a standardized test within 5 points of the true mean with 99% confidence. Assume that s 17 based on earlier studies. 6)The mean replacement time for a random sample of 20 washing machines is 10.9 years and the standard deviation is 2.7 years. Construct a 99% confidence interval for the standard deviation, o, o, the replacement times of all washing machines of this type. 7)The mean cost of textbooks for one class is greater than $160. Identify the type I and type ll errors for the hypothesis test of this claim 8)lf we do not reject the null hypothesis when the null hypothesis is in error, then we have made a 9)A machine dispenses a liquid drug into bottles in such a way that the standard deviation of the contents is 81 milliliters. A new machine is tested on a sample of 24 containers and the standard deviation for this sample group is found to be 26 milliliters. At the 0.05 level of significance, test the claim that the amounts dispensed by the new machine have a smaller standard deviation 10) A method currently used by doctors to screen women for possible breast cancer fails to detect cancer in 15% of the women who actually have the disease. A new method has been developed that be :。.。 researchers hope will be able to detect cancer more accurately. A random sample of 60 women known to have breast cancer were screened using the new method. Of these, the new method failed to detect cancer in 7. Calculate the test statistic used by the researchers for this test of hypothesis. Round to the nearest thousandth. 11)A local retailer claims that the mean waiting time is less than 6 minutes. A random sample of 20 waiting times has a mean of 4.2 minutes with a standard deviation of 2.1 minutes. At α : 0.01, test the retailer's claim. Assume the distribution is normally distributed. Round the test statistic to the nearest thousandth.

Answer 1