The number of books stored on the upper shelf of a bookshelf is 30% more than that of the lower shelf, and the number of books stored on the lower shelf is 15 fewer than that of the upper shelf. How many books are stored in the upper and lower shelves of this bookshelf?
一个书架上层存放图书的本数比下层多30%，下层存放的图书比上层少15本，这个书架上、下两层一共存放图书多少本？
<gadget id="calculator">30 / 100</gadget>
<output>3/10 = around 0.3</output>

<gadget id="calculator">15 / (3/10)</gadget>
<output>50</output>

<gadget id="calculator">50 + 50 + 15</gadget>
<output>115</output>

<result>115</result>