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Construct a 95% confidence interval for the population proportion of households where the women make the majority of the purchasing decisions. State the confidence interval, sketch the graph and calculate the error bound.

Short Answer

Expert verified

The confidence interval: CI:(0.532,0.668)

Margin of error =0.0679

Step by step solution

01

Given Information

A 95%confidence interval for the population proportion of households.

02

Explanation

Here we need to find the margin of errors,

That are,

Margin Of Error=Zα2×p′1−p′n

=Z0.052×1202001−120200200

=[1.96×0.03464]

=0.0679

Now we need to find the confidence interval

Confidence Interval=p′±Za2×p(1−p)n

=120200±Z0.052×1202001−120200200

=120200±1.96×0.03464

=[0.532,0.668]

The confidence interval is CI:(0.532,0.668).

The graph:

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