The Experimental Primary School carried out extracurricular activities. All the students in the school (4/13) participated in the literature and art class, (2/13) participated in the calligraphy class, and the number of art classes and literature and art classes was equally large. The rest take martial arts classes, what percentage of the total number of students in the school take part in martial arts classes?
实验小学开展课外活动，全校学生的(4/13)参加文艺班，(2/13)参加书法班，美术班和文艺班的人数同样多．剩下的参加武术班，参加武术班的人数占全校人数的几分之几？
<gadget id="calculator">4 / 13</gadget>
<output>4/13 = around 0.307692</output>

<gadget id="calculator">2 / 13</gadget>
<output>2/13 = around 0.153846</output>

<gadget id="calculator">1 - (4/13) - (2/13) - (4/13)</gadget>
<output>3/13 = around 0.230769</output>

<result>3/13 = around 0.230769</result>