Among the prime numbers within 10, any two numbers can be selected to form a fraction. What is the smallest fraction among them?
在10以内的质数中，任意挑选两个数就可以组成一个分数，其中最小的一个分数是多少．
<gadget id="calculator">2 / 7</gadget>
<output>2/7 = around 0.285714</output>

<result>2/7 = around 0.285714</result>