The consumer research firm Scarborough analyzed the 10 of Am

The consumer research firm Scarborough analyzed the 10% of American adults that are either Superbanked or Unbanked. Superbanked consumers are defined as U.S. adults who live in a a household that has multiple asset accounts at financial institutions, as well as some additional investments; Unbanked consumers are U.S. adults who live in a household that doesn\'t use a bank or credit union. By finding the 5% of Americans that are Superbanked, Scarborough identifies financially savvy consumers who might be open to diversifying their financial portfolios; by identifying the Unbanked , Scarsborough provides insight into the ultimate prospective client for banks and financial institutions. As part of its analysis, Scarsborough reported that 93% of Superbanked consumers use credit cards in the past three months as compared to 23% of Unbanked consumers. Suppose that these results were based on 1000 Superbanked consumers and 1000 Unbanked consumers. a) at the 0.01 level of significance , is there evidence of significant difference between the Superbanked and the Unbanked with respect to the proportion that use credit cards? b) find the p-value in (a) and interpret its meaning. c) construct and interpret a 99% confidence interval estimate for the difference between the Superbanked and Unbanked with respect to the proportion that use credit cards.

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