Confidence interval for this percentage

Reference no: EM131008868

A company manufacturing CDs is working on a new technology. A random sample of 703 Internet users were asked: "As you may know, some CDs are being manu- factured so that you can only make one copy of the CD af- ter you purchase it. Would you buy a CD with this technology, or would you refuse to buy it even if it was one you would normally buy?" Of these users, 64% responded that they would buy the CD.

a) Create a 90% confidence interval for this percentage.

b) If the company wants to cut the margin of error in half, how many users must they survey?

Reference no: EM131008868

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