Question

The table to the right shows the results of a survey in which 2558 adults from Country? A, 1104 adults from Country? B, and 1060 adults from Country C were asked if human activity contributes to global warming. Complete parts? (a), (b), and? (c). Adults who say that human activity contributes to global warming Country Upper A 60 ?% Country Upper B 87 ?% Country Upper C 93 ?% ?(a) Construct a 90 ?% confidence interval for the proportion of adults from Country Upper A who say human activity contributes to global warming. left parenthesis nothing comma nothing right parenthesis ?(Round to three decimal places as? needed.) ?(b) Construct a 90 ?% confidence interval for the proportion of adults from Country Upper B who say human activity contributes to global warming. left parenthesis nothing comma nothing right parenthesis ?(Round to three decimal places as? needed.) ?(c) Construct a 90 ?% confidence interval for the proportion of adults from Country Upper C who say human activity contributes to global warming. left parenthesis nothing comma nothing right parenthesis ?(Round to three decimal places as? needed.)

Answer 1

The statistical software output for this problem is:

One sample proportion summary confidence interval:
p : Proportion of successes
Method: Standard-Wald

90% confidence interval results:

Proportion	Count	Total	Sample Prop.	Std. Err.	L. Limit	U. Limit
p	1534.8	2558	0.6	0.0096862428	0.58406755	0.61593245

90% confidence interval results:

Proportion	Count	Total	Sample Prop.	Std. Err.	L. Limit	U. Limit
p	960.48	1104	0.87	0.010121544	0.85335154	0.88664846

90% confidence interval results:

Proportion	Count	Total	Sample Prop.	Std. Err.	L. Limit	U. Limit
p	985.8	1060	0.93	0.0078367783	0.91710965	0.94289035

Hence,

90% confidence intervals will be:

For A: (0.584, 0.616)

For B: (0.853, 0.887)

For C: (0.917, 0.943)