The ratio of boys to girls in grade six is 4:5, and there are 30 girls. This class accounts for 6% of the whole school. How many people are there in the whole school?
六年级男生与女生人数比是4：5，女生有30人，这个班人数占全校的6%，全校共多少人？
<gadget id="calculator">4 + 5</gadget>
<output>9</output>

<gadget id="calculator">5 / 9</gadget>
<output>5/9 = around 0.555556</output>

<gadget id="calculator">6 / 100</gadget>
<output>3/50 = around 0.06</output>

<gadget id="calculator">30 / (5/9) / (3/50)</gadget>
<output>900</output>

<result>900</result>