The school bought a batch of books and distributed 250 books to the third grade, and distributed 75 more books to the fourth grade than the third grade. How many books were bought in total for the third and fourth grades?
学校买来一批图书，分给三年级250本，分给四年级比三年级多75本，三四年级一共买来多少本？
<gadget id="calculator">250 + 75 + 250</gadget>
<output>575</output>

<result>575</result>