The difference between 1 and the reciprocal of a number is (7/9), what is the number.
1与一个数的倒数之差是(7/9)，这个数是多少．
<gadget id="calculator">7 / 9</gadget>
<output>7/9 = around 0.777778</output>

<gadget id="calculator">1 - (7/9)</gadget>
<output>2/9 = around 0.222222</output>

<gadget id="calculator">1 / (2/9)</gadget>
<output>9/2 = around 4.5</output>

<result>9/2 = around 4.5</result>