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Categorizing Inference Questions

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Categorizing Inference Questions

Categorizing Inference Questions1. Infants who cry easily may be more easily stimulated than others. This may be a sign of higher IQ. Child development researchers explored the relationship between the crying of infants 4 to 10 days old and their later IQ test scores. A snap of a rubber band on the sole of the foot caused the infants to cry. The researchers recorded the crying and measured its intensity by the number of peaks in the most active 20 seconds. They later measured the childrens IQ at age 3 years. The table below contains data from a random sample of 38 infants. Do these data provide convincing evidence that there is a positive linear relationship between the cry counts and IQ in the population of infants?

The researchers recorded the crying intensity by the number of peaks in the most active 20 seconds. They later measured the childrens IQ at age 3 years. The table below contains data from a random sample of 38 infants. Do these data provide convincing evidence that there is a positive linear relationship between the cry counts and IQ in the population of infants?2. Trace metals found in wells affect the taste of drinking water, and high concentrations can pose a health risk. Researchers measured the concentration of zinc (in milligrams per liter) near the top and the bottom of 10 randomly selected wells in a large region. The data are provided in the table below. Construct and interpret a 95% confidence interval for the mean difference in the zinc concentrations from these two locations in the wells.

A) meansB) the mean difference in the zinc concentrations from these two locations in the wellsC) one sample of 10 wells - two measurements at each wellResearchers measured the concentration of zinc (in milligrams per liter) near the top and the bottom of 10 randomly selected wells in a large region. The data are provided in the table below. Construct and interpret a 95% confidence interval for the mean difference in the zinc concentrations from these two locations in the wells.3. Researchers designed a survey to compare the proportions of children who come to school without eating breakfast in two low-income elementary schools. An SRS of 80 students from School 1 found 19 had not eaten breakfast. At School 2, an SRS of 150 students included 26 who had not had breakfast. More than 1500 students attend each school. Do these data give convincing evidence of a difference in the population proportions?

A) proportionsB) the true difference in the population proportions of children who come to school without eating breakfast in two low income elementary schoolsC) two samplesResearchers designed a survey to compare the proportions of children who come to school without eating breakfast in two low-income elementary schools. An SRS of 80 students from School 1 found 19 had not eaten breakfast. At School 2, an SRS of 150 students included 26 who had not had breakfast. More than 1500 students attend each school. Do these data give convincing evidence of a difference in the population proportions?4. Bottles of a popular cola are supposed to contain 300 milliliters of cola. There is some variation from bottle to bottle because the filling machinery is not perfectly precise. From experience, the distribution of the contents of the bottles is approximately normal. An inspector measures the contents of six randomly selected bottles from a single days production. Do these data provide convincing evidence that the mean amount of cola in all the bottles filled that day differs from the target value of 300 ml?