code: public float multipliedBy (Fraction fraction)
    {
      int newNumerator = numerator * fraction.getNumerator();
      int newDenominator = denominator * fraction.getDenominator();
      return (newNumerator/newDenominator);
    }
docs: Returns the float result of the multiplication of
  this fraction by the specified fraction.
  This fraction remains unchanged.
  @param fraction A Fraction.
  @return The result of the multiplication of this fraction by the specified
  one.