Calculation problem in Java

Question

I\'m having slight difficulty in performing a calculation in Java. Here is what I\'m trying to do -

((0.053800 * (500000/1000)) + 4) * 0.85

In m

Answer 1

The following is a much better approximation, which results in the same value in this case:

import java.math.BigDecimal;
import java.math.MathContext;

public class Test {
    public static void main(String[] args) {
        //double d = ((0.053800 * (500000/1000)) + 4) * 0.85;
        BigDecimal d = ((new BigDecimal(0.053800).multiply(new BigDecimal(500000).divide(new BigDecimal(1000)))).add(new BigDecimal(4))).multiply(new BigDecimal(0.85));
        System.out.println(d.round(MathContext.DECIMAL32));
    }
}

Answer 2

See my answer here for an explanation of what's going on.