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---
id: 5900f4a01000cf542c50ffb2
title: 'Problem 307: Chip Defects'
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challengeType: 5
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forumTopicId: 301961
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dashedName: problem-307-chip-defects
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---
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# --description--
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$k$ defects are randomly distributed amongst $n$ integrated-circuit chips produced by a factory (any number of defects may be found on a chip and each defect is independent of the other defects).
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Let $p(k,n)$ represent the probability that there is a chip with at least 3 defects. For instance $p(3,7) ≈ 0.0204081633$.
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Find $p(20\\,000, 1\\,000\\,000)$ and give your answer rounded to 10 decimal places in the form 0.abcdefghij
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# --hints--
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`chipDefects()` should return `0.7311720251` .
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```js
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assert.strictEqual(chipDefects(), 0.7311720251);
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```
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# --seed--
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## --seed-contents--
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```js
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function chipDefects() {
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return true;
}
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chipDefects();
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```
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# --solutions--
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```js
// solution required
```