How do I round my random number to a reasonable decimal?

I'm writing a program that is a quiz where the numbers in the problem are randomized. Then the user uses the random numbers to find the answer. They get a point each time they get a problem right. I keep getting outrageous decimals when the random numbers are generated. Here's the code:

import java.util.Scanner;

public class TriviaLab
{
    public static void main(String[] args)
    {
        Scanner kb = new Scanner(System.in);
        System.out.println("Welcome to the Trivia Game!");
        System.out.println("Please pick a category:");
        System.out.println("(Input 1 for Math or 2 for Geography)");
        String selection = kb.nextLine();
        if ( selection.equals("1") ) 
        {
            int counter = 0;
            System.out.println("Math Selected!\n");


            System.out.println("Question 1");
            //this is where the problem is: the doubles distance1 and time1 give me crazy huge decimals
            double distance1 = Math.random() * 5;
            double time1 = Math.random() * 5;
            double answer1 = distance1 / time1;
            double roundedanswer1 = Math.round(answer1 * 100.0) / 100.0;
            System.out.println("What is the magnitude of the average speed if you    travel " + distance1 + " meters in " + time1 + " seconds?");
            String aM1 = kb.nextLine();
            if (aM1.equals(roundedanswer1) )
            {
                System.out.println("Correct!");
                counter = counter + 1;
                System.out.println("Score=" + counter + "\n");
            }
            else
            {
                System.out.println("Incorrect!");
                System.out.println("The correct answer is " + answer1);
                System.out.println("Score=" + counter + "\n");
            }