online. The research firm decided to randomly sample households earning over $50,000 a year in the two cities and ask them if they purchased any groceries online last year. The random sample involved 150 Chicago households and 135 Milwaukee households. The results of the sample can be found in the file Online Groceries. 1. Construct a 95% confidence interval estimate for the difference between the two population proportions. 2. At the 0.10 level of significance, can the marketing research firm conclude that a greater proportion of households in Chicago earning over $50,000 annually buys more groceries online than do similar households in Milwaukee? Support your answer with the appropriate hypothesis test.
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