In 2004, a sample of 250 household in NY showed that 62 paid their monthly phone bills by debit card. in 2009 a sample of 350 household in the same city showed that 110 paid their monthly phone bill by debit card. Based on the sample data, can we conclude that there is difference between the population proportion of 2004 household and 2006 household in the same city?
a. determine the sample size are large enough.
b. conduct the appropriate hypothesis test. Report with p-value, would null hypothesis be rejected?
c. calculated pooled estimated for overall.