The fractional unit of a number is (1/7), and the fractional unit of its reciprocal is (1/9). What is this number?
一个数的分数单位是(1/7)，它的倒数的分数单位是(1/9)，这个数是多少．
<gadget id="calculator">9 / 7</gadget>
<output>9/7 = around 1.285714</output>

<result>9/7 = around 1.285714</result>