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?

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Determining the Minimum Sample Size Required
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Problem 33Multiple Choice

An inspection report reveals that $20 percent sign$ 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 $15$ 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?

$0.965$

Yes, the analyst can be reasonably sure of finding at least one defective unit

$0.452$

No, it is unlikely that any of the selected units will be defective

$0.735$

No, the probability is too low to expect a defective unit with confidence

$0.118$

No, the analyst will likely not find a defective unit

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