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Thread: How to round the numbers?

  1. #1
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    Default How to round the numbers?

    Hello,

    I'm new on this forum, I'm from Belgium, this is my first year IT and I'm 19 years old.
    I want that you help me with my problems about programming.

    The first problem is that the numbers don't round in IntelliJ.
    Example: (sorry, it's in Dutch)
    Geef de vorige kilometerstand: 125
    Geef de huidige kilometerstand: 900
    Geef het aantal getankte liters: 50
    Verbruik voor 775km: 6.451612903225806/100km

    That 6.4516..... is the problem, how can I make it 6.45/100km?

    If you want a picture of the program that I wrote, just ask it.
    thanks!


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    Default Re: How to round the numbers?

    Welcome to the forum! Please read this topic to learn how to post code in code or highlight tags and other useful info for new members.

    You could use the printf() method to format the output to the desired precision. The printf() method and the formatting needed to get the desired output can be a bit confusing at first, so give it a try and come back if you need help.

    If help is needed, please post the code you need help with correctly using code or highlight tags per the above link.

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    Default Re: How to round the numbers?

    This is the code, can you see what's wrong?
    But if you want, I can translate it in English.

     public class Verbruik {
        public static void main(String[] args) {
            int vorige, huidige;
            float aantalLiter, aantal, resultaat;
     
            Scanner keyboard = new Scanner(System.in);
     
            System.out.print("Geef de vorige kilometerstand: ");
            vorige = keyboard.nextInt();
            System.out.print("Geef de huidige kilometerstand: ");
            huidige = keyboard.nextInt();
            System.out.print("Geef het aantal getankte liters: ");
            aantal = keyboard.nextFloat();
     
            resultaat = huidige - vorige; // =aantal liters / resultaat * 100 //
            aantalLiter = (( aantal / resultaat )*100);
            System.out.printf("Verbruik voor " + resultaat + "km" + ": " + aantalLiter + " liter" + "/100km");
        }
    }
    Last edited by Javabeginner19; September 27th, 2014 at 07:27 AM.

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    Default Re: How to round the numbers?

    Yes I can. Did you review the API for the printf() method? Or you might try this Oracle tutorial.

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    Default Re: How to round the numbers?

    No I don't know what it is, can you just say what's wrong in the code?

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    Default Re: How to round the numbers?

    Telling you what's wrong and suggesting how to fix it is not as helpful to you as showing you how to figure it out yourself, so that's not my first choice. Don't give up on yourself yet. I'm not.

    What did you get from the tutorial page I suggested? That page gives specific examples you can use to make your printf() method more effective and do what you'd like. Try what is suggested there and come back with your changes.

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