To build a section of railway, the full length (1/10) was repaired on the first day, the full length (2/15) was repaired on the second day, and the rest was to be repaired on the third day. What fraction of the total length was repaired on the third day?
修一段铁路，第一天修了全长的(1/10)，第二天修了全长的(2/15)，第三天要把剩下的全修完．第三天修了全长的几分之几？
<gadget id="calculator">1 / 10</gadget>
<output>1/10 = around 0.1</output>

<gadget id="calculator">2 / 15</gadget>
<output>2/15 = around 0.133333</output>

<gadget id="calculator">1 - (1/10) - (2/15)</gadget>
<output>23/30 = around 0.766667</output>

<result>23/30 = around 0.766667</result>