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Complements
4. Probability / Complements / Problem 2
Problem 2

An inspection report reveals that 20%20\% of portable power banks produced in a certain factory do not meet safety standards. A quality analyst needs at least one defective unit for further testing. If the analyst randomly selects 1515 power banks from a larger batch, what is the probability that at least one of them is defective? Is this probability high enough for the analyst to reasonably expect at least one defective item?