Guangming Primary School donated 240 books to students in mountainous areas. Grade 4 donated 240 books, Grade 5 donated twice as much as Grade 4, Grade 6 donated 120 more books than Grade 5, and Grade 6 donated 240 books. How many books did Grade 6 donate?
光明小学为山区同学捐书，四年级捐240本，五年级捐的是四年级的2倍，六年级比五年级多捐120本，六年级捐多少本？
<gadget id="calculator">240 * 2</gadget>
<output>480</output>

<gadget id="calculator">480 + 120</gadget>
<output>600</output>

<result>600</result>