Why is my code giving me the wrong answer to this math q uestion?

Question

My apologies if the title is a bit confusing I had some trouble trying to word what I was trying to say.

Here is my code:

public class Assignment3 {

    public static void main(String[] args) {
        int A = 100;
        int B = 20;
        int C = 30;
        int X = 4 * A;
        int Y = 3 * (B + C);
        int Z = X / Y;

        System.out.println("The value of A is " + A + ".");
        System.out.println("The value of B is " + B + ".");
        System.out.println("The value of C is " + C + ".");
        System.out.println("The answer is " + Z + ".");

    }

}

It keeps giving me 2 as the answer when I know the answer is 2.6 repeating. Any ideas why and how I can fix it? Thanks in advance.

Now you know to use `float` or `double` for fractional numbers. But those can be inaccurate. When you need accuracy, such as for money, use `BigDecimal`. — Basil Bourque, Jul 02 '16 at 02:59

score 3 · Answer 1 · answered Jul 02 '16 at 01:23

3

Both X and Y are integers (non decimal values). If you perform integer division, the decimal is truncated, leading to an unexpected answer.

answered Jul 02 '16 at 01:23

Aditya R

417
4
13

so what should I change them to? – cpitt6477 Jul 02 '16 at 01:27
Nevermind I changed the last 3 to floats and now it works. Thanks! – cpitt6477 Jul 02 '16 at 01:28

score 1 · Answer 2 · answered Jul 02 '16 at 01:28

1

Two things you have to do. - Change the type of Z to float. - Cast either A or B to float in the division, as both of them are integers.

Try this and you will get the correct result:

float Z = (float) X / Y;

answered Jul 02 '16 at 01:28

Nguyen Tuan Anh

1,016
7
14

Thanks for the help! – cpitt6477 Jul 02 '16 at 01:29
No problem. Glad it helped. – Nguyen Tuan Anh Jul 02 '16 at 01:30

Why is my code giving me the wrong answer to this math q uestion?

2 Answers2