ne survey of 880 drivers asked, "Recalling the last ten traffic-lights you drove through, how many of them were red when you entered the intersection?...

A random digit dialing telephone survey of 880 drivers asked, "Recalling the last ten traffic-lights you drove through, how many of them were red when you entered the intersection?" Of the 880 respondents, 171 admitted that at least one light had been red. Follow the four-step process to construct a 95% confidence interval. State, Plan, Do, Conclude.