Statistics published by Monitoring the Future (www.monitorin…

Statistics published by Monitoring the Future (www.monitoringthefuture.org) show that the percentage of 12th graders who have used marijuana in 2003 is 46.1% versus 36.7% in 1991. A 95% confidence interval for p2003 – p1991 is given by (0.08, 0.11) where p2003 is the proportion of 12th graders who had used marijuana in 2003 and p1991 is the proportion of 12th graders who had used marijuana in 1991. Based on this interval, what can you conclude about the proportion of 12th graders who have used marijuana in 2003 versus 1991?

According to a recent Gallup poll, “Americans’ current opini…

According to a recent Gallup poll, “Americans’ current opinions of Planned Parenthood are considerably less favorable than they were in 1993” at 81%.  In the recent poll of 1015 adults, 60% viewed Planned Parenthood favorably.  Is there enough evidence to support the claim at  Do a hypothesis test and interpret your decision for the hypothesis test

A survey of shoppers is planned to determine what percentage…

A survey of shoppers is planned to determine what percentage use credit cards.  Prior surveys suggest 63% of all shoppers use credit cards.  How many randomly selected shoppers must we survey in order to estimate the proportion of shoppers who use credit cards to within 4% with 95% confidence?

A survey of shoppers is planned to determine what percentage…

A survey of shoppers is planned to determine what percentage use credit cards.  Prior surveys suggest 63% of all shoppers use credit cards.  How many randomly selected shoppers must we survey in order to estimate the proportion of shoppers who use credit cards to within 4% with 95% confidence?

Statistics published by Monitoring the Future (www.monitorin…

Statistics published by Monitoring the Future (www.monitoringthefuture.org) show that the percentage of 12th graders who have used marijuana in 2003 is 46.1% versus 36.7% in 1991. A 95% confidence interval for p2003 – p1991 is given by (0.08, 0.11) where p2003 is the proportion of 12th graders who had used marijuana in 2003 and p1991 is the proportion of 12th graders who had used marijuana in 1991. Based on this interval, what can you conclude about the proportion of 12th graders who have used marijuana in 2003 versus 1991?

Different cereals are randomly selected for a sample, and th…

Different cereals are randomly selected for a sample, and the sugar content is obtained for each cereal, with the results of the sample given below.  Use a 0.05 significance level to test the claim of a cereal lobbyist that the mean for all cereals is less than 0.3 g. Do a hypothesis test and interpret your decision for the hypothesis test.   0.03 0.24 0.30 0.47 0.43 0.07 0.47 0.13 0.44 0.39 0.48 0.17 0.13 0.09 0.45 0.43