A school newly purchased 480 literary books and scientific books. If (2/5) of the literary books plus 30 books are replaced with scientific books, the ratio of literary books to scientific books is 1:3. How many literary books are there?
某校新买文艺书和科技书共480本，如果把文艺书本数的(2/5)再加上30本换成科技书后，文艺书与科技书的比是1：3，求新买的文艺书有多少本？
<gadget id="calculator">1 / 3</gadget>
<output>1/3 = around 0.333333</output>

<gadget id="calculator">(1/3) * 480</gadget>
<output>160</output>

<gadget id="calculator">(1/3) * 30</gadget>
<output>10</output>

<gadget id="calculator">30 + 160 + 10</gadget>
<output>200</output>

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

<gadget id="calculator">(1/3) * (2/5)</gadget>
<output>2/15 = around 0.133333</output>

<gadget id="calculator">(1/3) - (2/5) - (2/15)</gadget>
<output>-1/5 = around -0.2</output>

<gadget id="calculator">1 + (-1/5)</gadget>
<output>4/5 = around 0.8</output>

<gadget id="calculator">200 / (4/5)</gadget>
<output>250</output>

<result>250</result>