The school ordered books for the students, a total of 240 books were ordered for grades 1-3, and 55 books for each grade of grades 4-6. How many books did the school order for students in total?
学校为学生订图书，1-3年级一共订了240本，4-6年级每个年级订55本，学校一共为学生订了多少本图书？
<gadget id="calculator">55 * 3</gadget>
<output>165</output>

<gadget id="calculator">165 + 240</gadget>
<output>405</output>

<result>405</result>