1. A Southern Cross Health Society survey of 1500 adult members found that 60% respondents had had a cholesterol check in the previous 12 months and 90% had had their blood pressure checked. (a) Calculate the margin of error for this survey and use it to calculate a 95% confidence interval for the percentage of adult New Zealanders with health insurance who will have had a cholesterol check during the previous 12 months. Interpret the meaning of this confidence interval in words.
