standard error of proportion, se = where n is the sample size
z value for 98% confidence interval = 2.33
Now,
Margin of error, E = z * se
E = z *
=> n = (z / E)2 * p(1-p)
n = (2.33 / 0.03)2 * 0.28 * (1-0.28) = 1216.074
n = 1216 (Rounding to nearest integer)
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