为了避免使用浮点数表示分数（因为在计算机中使用浮点数会涉及到近似），我们可以使用两个整数来表示分数的分子和分母。下面是示例代码：

class Fraction:
    def __init__(self, numerator, denominator):
        self.numerator = numerator
        self.denominator = denominator
    
    def __str__(self):
        return f"{self.numerator}/{self.denominator}"
    
    def __mul__(self, other):
        return Fraction(self.numerator * other.numerator, self.denominator * other.denominator)
    
    def __add__(self, other):
        if self.denominator == other.denominator:
            return Fraction(self.numerator + other.numerator, self.denominator)
        else:
            return Fraction(self.numerator * other.denominator + other.numerator * self.denominator, self.denominator * other.denominator)
    
    def __sub__(self, other):
        if self.denominator == other.denominator:
            return Fraction(self.numerator - other.numerator, self.denominator)
        else:
            return Fraction(self.numerator * other.denominator - other.numerator * self.denominator, self.denominator * other.denominator)
    
    def __truediv__(self, other):
        return Fraction(self.numerator * other.denominator, self.denominator * other.numerator)

以上代码使用类 Fraction 来表示分数，其中的运算符重载方法 __mul__、__add__、__sub__、__truediv__ 等可以对分数进行基本的数学运算。如果需要，还可以添加其他运算符重载方法。通过这种方式，我们就可以使用整数来表示分数，而不必担心浮点数近似带来的问题。