# Finding Confidence Intervals for Proportions: Formula & Example

Instructions:

question 1 of 3

### In the formula for the confidence interval, why do we add and subtract z * s_p-hat from p-hat?

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### 2. What is the margin of error?

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Practice finding confidence intervals with this combination quiz and worksheet. You will be asked about population proportions and sample proportions, as well as how to find a margin of error.

## Quiz & Worksheet Goals

• The formula for margin of error
• Expressing population and sample proportions
• The definition of margin of error
• Point estimates

## Skills Practiced

• Defining key concepts - be sure that you can accurately describe the margin of error in words
• Information recall - remember what you have learned about the mathematical formula for margin of error