In a survey of 800 US adults 90 are making the minimum payme

In a survey of 800 U.S. adults, 90 are making the minimum payment on their credit card. With a 99% confidence interval for the population proportion, what is the margin of error?

Solution

Here p hat=90/800=0.11

The margin of error is:

z0.99*sq rt(0.11*0.89/800)

=1.645*0.01

=0.01645