There are 360 girls in Guangming Primary School, accounting for 40% of the total number of students in the school, and the number of sixth grade students accounts for 20% of the total number of students in the school. How many students are there in grade six?
光明小学有女生360人，占全校总人数的40%，六年级学生人数占全校总人数的20%．六年级有学生多少人？
<gadget id="calculator">40 / 100</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">360 / (2/5)</gadget>
<output>900</output>

<gadget id="calculator">20 / 100</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">900 * (1/5)</gadget>
<output>180</output>

<result>180</result>