Lemma
MediumConfidence intervals
OpenStax, Statistics §8.3 A Population Proportion · Exercise 34 · Statistics · Confidence intervals

A Population Proportion · Exercise 34

Insurance companies are interested in knowing the population percentage of drivers who always buckle up before riding in a car.

(a) When designing a study to determine this population proportion, what is the minimum number you would need to survey to be 95 percent confident that the population proportion is estimated to within 0.03?
(b) If it were later determined that it was important to be more than 95 percent confident and a new survey was commissioned, how would that affect the minimum number you would need to survey? Why?

~8 minWritten answer · check your work with Lemma

OpenStax, Statistics · §8.3 A Population Proportion · Exercise 34

Stuck? A gentle nudge

No hints for this one.

Something off?
Workspace
Your working

Check your full solution

Attach photos of your pages (up to 3) or one PDF — or check what you typed above. Lemma reads the work and verifies the reasoning, not just the answer.

Your first check today doesn't need an account.

Your photos and PDFs are read once and not stored — only the transcription is kept.