Solution:
Formula for calculation of 99% confidence interval is given by:
=
P= Sample Proportion
N =Sample Size
Also,Number of voters who vote online= 19 % of 1300=19 × 13=247
Sample Population= =0.19
Z value for 99% confidence interval=2.58
The number of voters who vote online, who are in the 99% confidence interval for the percent of all voters who would prefer to vote online=
So, Percent of voters , who are in the 99% confidence interval for the percent of all voters who would prefer to vote online= 100 × 0.2180 or 100 × 0.1619=21.80 % or 16.19 %
That is between, 16.19 % and 21.80 %.
→→Option (A) 19.8 % and Option (B)17.4 % are in 99 % confidence intervals.
