In the fourth grade, there are 30 good students, which is (1/6) of the whole grade, and the fourth grade accounts for (2/9) of the whole school. How many students are there in the school?
四年级有三好学生30人，是全年级人数的(1/6)，四年级人数占全校人数的(2/9)．全校有学生多少人？
<gadget id="calculator">1 / 6</gadget>
<output>1/6 = around 0.166667</output>

<gadget id="calculator">2 / 9</gadget>
<output>2/9 = around 0.222222</output>

<gadget id="calculator">30 / (1/6) / (2/9)</gadget>
<output>810</output>

<result>810</result>