25.
p=0.181
np(1-p)=341.8 > (or equal to) 10; sample is less than 5%
lower=0.168, upper=0.194
90% confidence that the proportion of adults 18 years and older who have donated blood is between 0.168 and 0.194
26.
p=0.430
np(1-p)=282.60 > (or equal to) 10; sample is less than 5%
lower=0.402, upper=0.459
95% confidence that the proportion of workers 25 years and older who have less that $10,000 in savings is between 0.402 and 0.459
27.
p=0.519
np(1-p)=250.39 > (or equal to) 10; sample is less than 5%
lower=0.488, upper=0.550
yes, it is possible for the supermajority to believe this because the true proportion may not be included in the confidence interval, but no it is not likely
lower=0.450, upper=0.512
28.
p=0.750
np(1-p)=192 > (or equal to) 10; sample is less than 5%
lower=0.715, upper=0.785
yes, it is possible for the proportion to be below 70% because the true proportion may not be included in the confidence interval, but no it is not likely
lower=0.215, upper=0.285
29.
lower=0.071, upper=0.151
lower=0.058, upper=0.164
level of confidence increases as margin of error increases