A total of 498 participants responded to a survey questionnaire. I want to be ascertain that the sample size of 498 reflects the opinions of the true population (say 1,000,000).
I used an online calculator that shows that the margin of error is 4% population size: 1000,000 confidence level (%): 95 Your sample size: 498
The margin of error is 4% (online calculator)
Manual Calculation: Group A: 123, Group B: 70, Group C:37, Group D:40, Group E:74, Group F:15, Group G:15, Group H:15, Group I:28, Group J:81
Count, N: 10 Sum, Σx: 498 Mean, x̄: 49.8 Variance, s2: 1299.2888888889 std deviation, s = √1299.2888888889 s = 36.04565006889
Standard Error, sx̄ = s / √N = 36/ √10 =11.39863539591
Margin of Error = critical value x Standard Error = 1.96 x 11.39863539591 = 22.341
Please advise why the margin of error (using manual calculation) results in 22.341