Confidence Interval for population proportion

Confidence Interval for population proportion

Author: Bob Kibler
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CI for proportion


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Do I get it?

Answers to "Do I get it?"

The sample proportion is 0.18 (18 divided by 100)

The z-score is 1.64 (Remember that 5% off of both sides is removed)

The margin of error is 0.06

The confidence interval is (0.12,0.24)

The confidence interval means that:

We are 90% confidence that the actually proportion of houses that utilize the bulk trash pick up in a given month is between 0.12 and 0.24 (or 12-24%)