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A grocery store chain has been tracking data on the number of shoppers that use coupons. The data shows that 71% of all shoppers use coupons. 18 times out of 20 these results were considered accurate to within 2.5%. What is the confidence level?

User Monomachus
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2 Answers

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Final answer:

The confidence level is 95% in this case.

Step-by-step explanation:

The confidence level represents the level of certainty that the results obtained from a sample are accurate and can be generalized to the entire population. In this case, the confidence level is not explicitly stated in the question, but it can be inferred from the information provided. It is mentioned that 18 times out of 20, the results were considered accurate to within 2.5%. This suggests that the confidence level is 95%, meaning that there is a 95% chance that the true proportion of shoppers using coupons lies within 2.5% of the observed proportion.

User Hortitude
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5 votes
What's the sample size?
User Scottyab
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