The First National Bank of Wilson has 660 checking account customers. A recent sample of 60 of these customers showed 35 have a Visa card with the bank. Construct the 99% confidence interval for the proportion of checking account customers who have a Visa card with the bank. (Use z Distribution Table.) (Round your answers to 3 decimal places.)

Sample proportion = 35 / 60 = 0.583
99% confidence interval for p is
 Z/2 * sqrt [ ( 1  ) / n ] < p < + Z/2 * sqrt [ ( 1  ) / n ]
0.583  2.576 * sqrt [ 0.583 ( 1  0.583) / 60 ] < p < 0.583 + 2.576 * sqrt [ 0.583 ( 1  0.583) / 60 ]
0.419 < p < 0.747
99% CI is between 0.419 and 0.747
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