The total time for the Mathematics Final Exam is 90 minutes. Xiao Ming spends (1/4) doing application questions, (2/9) doing statistics and operation questions, and the rest is time doing other questions. What percentage of the total exam time did Xiao Ming spend on other questions?
数学期末考试的总时间为90分钟．小明做应用题的时间占(1/4)，做统计与操作题的时间共占(2/9)，剩下的是做其它题的时间．小明做其它题的时间占考试总时间的几分之几？
<gadget id="calculator">1 / 4</gadget>
<output>1/4 = around 0.25</output>

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

<gadget id="calculator">1 - (1/4) - (2/9)</gadget>
<output>19/36 = around 0.527778</output>

<result>19/36 = around 0.527778</result>