Li Gang reads a book. He reads (1/4) on the first day and 60 pages on the second day. At this time, the ratio of the number of pages he has read to the number of pages he has not read is 2:3. How many pages are there in this book?
李刚看一本书，第一天看了(1/4)，第二天看了60页，这时看了的与未看的页数比是2：3，这本书一共有多少页？
<gadget id="calculator">2 + 3</gadget>
<output>5</output>

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

<gadget id="calculator">1 / 4</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">(2/5) - (1/4)</gadget>
<output>3/20 = around 0.15</output>

<gadget id="calculator">60 / (3/20)</gadget>
<output>400</output>

<result>400</result>