How large a sample must be drawn so that a 98 confidence Int

How large a sample must be drawn so that a 98% confidence Interval for p will have a margin of error equal to 1.5? Round up the answer to the nearest Integer. A sample size of Is needed to be drawn In order to obtain a 98% confidence Interval with a margin of error equal to 1.5.

Solution

Margin of error = z(std error) =2.33(sigma/rtn) = 1.5

i.e. rt n = 2.33(17.2)/1.5 = 26.72

n = 713.88

Hence sample size should be atleast 714.