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Hi does anyone have any suggestions on how to solve this problem? To construct a circuit a student needs, among others, 12 chips of a certain type. The student knows that 4% of these chips are defective. How many chips have to be provided so that, with a probability of not less than 0.9, the student has a sufficient number of nondefective chips in order to be able to construct the circuit?

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Hint: The distribution of the number of good chips in the sample is binomial. You'll probably just need a few more than 12, so try n=12, 13, 14, ...

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