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# How to use the Math.random() method in Java Educative Answers Team

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The Math.random() method returns a pseudorandom number of data type double. The range of this random number is given by the following limit:

$0.0\leq x <1.0$
where $x$ is the random number.

This method belongs to the java.lang.Math class, so you need to import this class before implementing​ this method.

Using the code snippet below we can generate a random number of type double. Give it a try!

import java.lang.Math; //importing Math class in Javaclass MyClass {   public static void main(String args[])   {     double rand = Math.random(); // generating random number     System.out.println("Random Number: " + rand);  // Output is different everytime this code is executed   } } ## Using random() method for a range

Mostly the random() method is used to generate random numbers between a specific range. Using this method, we define a method named randomWithRange, that returns an integer with a user-defined range.

int randomWithRange(int min, int max){   int range = (max - min) + 1;        return (int)(Math.random() * range) + min;}

Since the random() method produces a double number, we need to cast it in an integer, just as shown in the example below:

class MyClass {  int randomWithRange(int min, int max){   //defining method for a random number generator    int range = (max - min) + 1;         return (int)(Math.random() * range) + min;  }    public static void main( String args[] ) {    MyClass obj1=new MyClass();       // creating an object of MyClass    int rand=obj1.randomWithRange(1,100); // range is from 1 to 100     System.out.println(rand);  }}

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