The fifth grade of Hongguang Primary School carried out extracurricular interest activities. (7/20) students participated in the chorus team, (1/4) students participated in the calligraphy group, and the rest of the students participated in the sports group. How much?
红光小学五年级开展课外兴趣活动，有(7/20)的学生参加合唱队，(1/4)的学生参加书法组，其余学生参加了体育组，参加体育组的人数占总人数的几分之几？
<gadget id="calculator">7 / 20</gadget>
<output>7/20 = around 0.35</output>

<gadget id="calculator">1 / 4</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">1 - (7/20) - (1/4)</gadget>
<output>2/5 = around 0.4</output>

<result>2/5 = around 0.4</result>