Xiaogang reads a storybook. On the first day, he read 40% of the whole book. On the second day, he read 10 pages more than the first day, and there are 30 pages left. How many pages does this storybook have?
小刚读一本故事书，第一天读了全书的40%，第二天比第一天多读10页，还剩下30页没有读，这本故事书一共有多少页？
<gadget id="calculator">30 + 10</gadget>
<output>40</output>

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

<gadget id="calculator">40 / (1/5)</gadget>
<output>200</output>

<result>200</result>