On Arbor Day, Class 1 and Class 2 of the sixth grade went to plant trees. There were 45 students in Class 1, and a total of 270 trees were planted; there were 48 students in Class 2, and an average of 5 trees were planted per person. How many trees are planted per class on average?
植树节时，六年级一班和二班去植树，一班有45人，一共植树270棵；二班有48人，平均每人植树5棵．平均每班植树多少棵？
<gadget id="calculator">48 * 5</gadget>
<output>240</output>

<gadget id="calculator">270 + 240</gadget>
<output>510</output>

<gadget id="calculator">510 / 2</gadget>
<output>255</output>

<result>255</result>