A Gallup poll found that only 28%of American adults expect to inherit money or valuable possessions from a relative. The poll’s margin of error was ±3 percentage points at a 95%confidence level. This means that

a. the poll used a method that gets an answer within 3% of the truth about the population 95%of the time.

b. the percent of all adults who expect an inheritance must be between 25%and 31%.

c. if Gallup takes another poll on this issue, the results of the second poll will lie between 25%and 31%.

d. there’s a 95% chance that the percent of all adults who expect an inheritance is between

25% and 31%.

e. Gallup can be 95% confident that between 25% and 31% of the sample expect an inheritance.

Short Answer

Expert verified

Option (b) is correct.

Step by step solution

01

Given Information

It is given that (p^)=28%=0.28

(E)=3%=0.03

02

Concept Used

Formula to be used:

CI=p^±E

03

Calculation

Confidence Interval is calculated as:

CI=p^±E==0.28±0.03

CI=(0.25,0.31)

Hence, option (b) is correct.

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