There are three classes in the fifth grade of Jianxin Primary School, the first class accounts for (3/8) of the total number of fifth graders, and the second class accounts for (3/10) of the total number of fifth graders. What percentage of the total number of students in the third class accounted for the fifth grade?
建新小学五年级有三个班，一班占五年级总人数的(3/8)，二班占五年级总人数的(3/10)．三班占五年级总人数的几分之几？
<gadget id="calculator">3 / 8</gadget>
<output>3/8 = around 0.375</output>

<gadget id="calculator">3 / 10</gadget>
<output>3/10 = around 0.3</output>

<gadget id="calculator">1 - (3/8) - (3/10)</gadget>
<output>13/40 = around 0.325</output>

<result>13/40 = around 0.325</result>