A number of people form 10 circles, one trap for one circle, and the number of people in each circle is reduced by 3 from the outside to the inside. If there are 30 people in the innermost circle, how many people are there in total?
若干人围成10个圈，一个圈套一圈，从外面向内各圈人数依次少3，如果最内圈有30人，共有多少人？
<gadget id="calculator">10 - 1</gadget>
<output>9</output>

<gadget id="calculator">9 * 3</gadget>
<output>27</output>

<gadget id="calculator">30 + 27</gadget>
<output>57</output>

<gadget id="calculator">30 + 57</gadget>
<output>87</output>

<gadget id="calculator">10 / 2</gadget>
<output>5</output>

<gadget id="calculator">87 * 5</gadget>
<output>435</output>

<result>435</result>