Xiaogang reads a storybook. He reads 40% of the whole book on the first day and 30% of the whole book on the second day. There are 60 pages left. How many pages are there in this storybook?
小刚读一本故事书，第一天读了全书的40%，第二天读了全书的30%，还剩60页没读，这本故事书有多少页？
<gadget id="calculator">30 / 100</gadget>
<output>3/10 = around 0.3</output>

<gadget id="calculator">40 / 100</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">1 - (3/10) - (2/5)</gadget>
<output>3/10 = around 0.3</output>

<gadget id="calculator">60 / (3/10)</gadget>
<output>200</output>

<result>200</result>