Guangming Primary School organizes fourth and fifth grade students to donate books to Hope Primary School. There are 11 classes in the fourth grade, with an average of 207 books donated per class, and 9 classes in the fifth grade, with an average of 230 books donated per class. How many books do you donate?
光明小学组织四、五年级的学生给希望小学捐书，四年级共有11个班，平均每班捐书207本，五年级共有9个班，平均每个班捐书230本，两个年级共捐书多少本？
<gadget id="calculator">207 * 11</gadget>
<output>2_277</output>

<gadget id="calculator">230 * 9</gadget>
<output>2_070</output>

<gadget id="calculator">2_277 + 2_070</gadget>
<output>4_347</output>

<result>4_347</result>