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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 margin of error?

2 Answers

4 votes

Answer:

0.025

Explanation:

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User Shrikant Mavlankar
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6.9k points
4 votes
Given:
71% of all shoppers use coupons.
18 times out of 20 these results were considered accurate to within 2.5%.

71% represents the percentage of the whole population which is all the shoppers of grocery store.

18 times out of 20 refers to the confidence interval of the results.

18/20 * 100% = 90%

2.5% is the range of accuracy in the 90% confidence interval.

The margin of error is 2.5%.
User Stotastic
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7.7k points