Xincheng Primary School donated 350 books for the "Earthquake-stricken Areas". The fifth grade donated 350 books, just 2/5 more than the sixth grade. How many books did the sixth grade donate?
新城小学为"地震灾区捐书"，五年级捐了350本，正好比六年级多捐(2/5)，六年级捐书多少本？
<gadget id="calculator">2 / 5</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">1 + (2/5)</gadget>
<output>7/5 = around 1.4</output>

<gadget id="calculator">350 / (7/5)</gadget>
<output>250</output>

<result>250</result>