I hope that the students in Class 5 and 4 of the primary school are in physical education class. Those who play basketball account for (2/5) of the total number of students, those who play football account for (1/3) of the whole class, and the rest of the students are skipping rope. What fraction of the whole class?
希望小学五4班的同学上体育课，玩篮球的占了总人数的(2/5)，玩足球的占了全班的(1/3)，剩下的同学在跳绳，跳绳的同学占全班的几分之几？
<gadget id="calculator">2 / 5</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">1 / 3</gadget>
<output>1/3 = around 0.333333</output>

<gadget id="calculator">1 - (2/5) - (1/3)</gadget>
<output>4/15 = around 0.266667</output>

<result>4/15 = around 0.266667</result>