MathTools.java

package br.teste.junit5;

public class MathTools {
   public static double convertToDecimal(int numerator, int denominator) {
       if (denominator == 0) {
           throw new IllegalArgumentException("Denominador é 0!");
       }
           return (double)numerator / (double)denominator;
      }

   public static boolean isEven(int number) {
           return number % 2 == 0;
 }
}