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Please note that this question consists of three parts. You…

Please note that this question consists of three parts. You may use MINITAB to find a final answer. However you MUST show all the mathematical work to get to the final answer. Just giving the answer without adequate work/explanation may result in zero for the question.  In a college town, there is a central location where people can drop-off miscellaneous plastics that were not collected in regular weekly pick-ups. The authorities want to study the true proportion of households using the drop-off location for plastic recycling. They have taken a random sample of 120 households and asked them if they use drop-off facility. Of the sampled households, 45 said they use the drop-off bins.  Find a 95% confidence interval for the true proportion of households using the drop-off location for plastic recycling. Interpret the above calculated interval in the context of the problem. The authorities believe about 35% of the households in the town are using the drop-off location for plastic recycling. Based on the interval in part 1, are the authorities correct? Explain.

The administration of a large university is planing on incre…

The administration of a large university is planing on increasing the student fees with the intention of using majority of the funds towards renovations in the football stadium. In a random sample of 60 students, 38 support of the idea. A 90% confidence interval for the true proportion of students who oppose this idea is 

A private courier company claims that their average delivery…

A private courier company claims that their average delivery time within a major city is under 90 minutes. A customer protection agency is investigating the complaints from customers about long delivery times. What are the correct hypotheses to answer the agency’s question?