Two classes in the fourth grade donated money to the Hope Project. The first class donated a total of 285 yuan, and the second class donated a total of 363 yuan. There are 72 students in the two classes. How much is the average donation per person?
四年级两个班为希望工程捐款，一班共捐285元，二班共捐363元，两个班共72人，平均每人捐多少元？
<gadget id="calculator">285 + 363</gadget>
<output>648</output>

<gadget id="calculator">648 / 72</gadget>
<output>9</output>

<result>9</result>