Uncle Xu rode a bicycle from A to B. He traveled the whole distance (1/3) in the first hour, 2/9 in the second hour, and the same amount in the third hour as in the second hour. What fraction of the whole journey was done in these three hours?
徐叔叔骑自行车从甲地到乙地，第一小时行了全程的(1/3)，第二小时行了全程的(2/9)，第三小时与第二小时行的同样多．这三个小时一共行了全程的几分之几？
<gadget id="calculator">1 / 3</gadget>
<output>1/3 = around 0.333333</output>

<gadget id="calculator">2 / 9</gadget>
<output>2/9 = around 0.222222</output>

<gadget id="calculator">(1/3) + (2/9) + (2/9)</gadget>
<output>7/9 = around 0.777778</output>

<result>7/9 = around 0.777778</result>