43 lines
842 B
Markdown
43 lines
842 B
Markdown
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---
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id: 5900f4a01000cf542c50ffb2
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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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`euler307()` should return 0.7311720251.
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```js
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assert.strictEqual(euler307(), 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 euler307() {
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return true;
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}
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euler307();
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```
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# --solutions--
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```js
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// solution required
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```
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