Introduction to JavaScript – Libraries – Instance methods, by definition, require that you create an instance before you can use them. What if you want to call a method without an instance? That’s where JavaScript libraries come in. Libraries contain methods that you can call without creating an instance.

One such collection contains mathematical methods, aptly named the **Math** library.

Let’s see how you call the **.random()** method from the **Math** library:

console.log(Math.random()); // random number between 0 and 1

In the example above, we called the **.random()** method by appending the library name with a period, the name of the method, and opening (**(**) and closing (**)**) parentheses. This method returns a random number between 0 and 1. This code prints a random number between 0 and 1.

To generate a random number between 0 and 50, we could multiply this result by 50, like so:

Math.random() * 50;

The answer in the example above will most likely be a decimal. To ensure an answer is a whole number, JavaScript provides a built-in method called **Math.floor()**. **Math.floor()** takes a decimal number, and rounds down to the nearest whole number. You can use **Math.floor()** to round a random number like this:

Math.floor(Math.random() * 50);

In this case:

**Math.random**generates a random number between 0 and 1.- We then multiply that number by 50, so now we have a number between 0 and 50.
- Then,
**Math.floor**rounds the number down to the nearest whole number.

Play with the code below to continue practising your coding skills with math.random and math.floor. Try to make your program generate a random number from 0 to 99.

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