70 lines
1.5 KiB
Markdown
70 lines
1.5 KiB
Markdown
---
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id: cf1111c1c11feddfaeb9bdef
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title: Generate Random Fractions with JavaScript
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challengeType: 1
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videoUrl: 'https://scrimba.com/c/cyWJJs3'
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forumTopicId: 18185
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---
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# --description--
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Random numbers are useful for creating random behavior.
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JavaScript has a `Math.random()` function that generates a random decimal number between `0` (inclusive) and not quite up to `1` (exclusive). Thus `Math.random()` can return a `0` but never quite return a `1`
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**Note**
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Like [Storing Values with the Equal Operator](/learn/javascript-algorithms-and-data-structures/basic-javascript/storing-values-with-the-assignment-operator), all function calls will be resolved before the `return` executes, so we can `return` the value of the `Math.random()` function.
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# --instructions--
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Change `randomFraction` to return a random number instead of returning `0`.
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# --hints--
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`randomFraction` should return a random number.
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```js
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assert(typeof randomFraction() === 'number');
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```
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The number returned by `randomFraction` should be a decimal.
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```js
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assert((randomFraction() + '').match(/\./g));
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```
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You should be using `Math.random` to generate the random decimal number.
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```js
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assert(code.match(/Math\.random/g).length >= 0);
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```
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# --seed--
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## --after-user-code--
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```js
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(function(){return randomFraction();})();
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```
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## --seed-contents--
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```js
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function randomFraction() {
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// Only change code below this line
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return 0;
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// Only change code above this line
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}
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```
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# --solutions--
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```js
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function randomFraction() {
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return Math.random();
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}
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```
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