The sixth grade students of Jiayi School participated in math and English competitions. The number of participants accounted for (2/5) of the total number of participants in the whole grade. 12 people. How many people are there in the sixth grade in this school?
佳一学校六年级的学生参加数学、英语竞赛．参赛人数占全年级总人数的(2/5)，参加英语竞赛的人数是参赛人数的(2/5)，参加数学竞赛的人数是参赛人数的(3/4)，两科都参加的有12人．这个学校六年级一共有多少人？
<gadget id="calculator">2 / 5</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">3 / 4</gadget>
<output>3/4 = around 0.75</output>

<gadget id="calculator">(3/4) - 1</gadget>
<output>-1/4 = around -0.25</output>

<gadget id="calculator">(2/5) + (-1/4)</gadget>
<output>3/20 = around 0.15</output>

<gadget id="calculator">12 / (3/20) / (2/5)</gadget>
<output>200</output>

<result>200</result>