The sixth grade of a certain school held a composition and mathematics competition. The number of participants accounted for 40% of the total number of students in the whole grade. There are 12 people participating in the event. How many people are there in the sixth grade?
某校六年级举行作文和数学竞赛，参赛人数占全年级总人数的40%，参加作文竞赛的占竞赛人数的(2/5)，参加数学竞赛的占竞赛人数的(3/4)，两项都参加的有12人，六年级共有多少人？
<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">40 / 100</gadget>
<output>2/5 = around 0.4</output>

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

<result>200</result>