Hope Primary School carried out tree planting activities. There were 243 students in the fifth grade and 257 students in the sixth grade. On average, each person planted 4 trees. How many trees did they have in total?
希望小学开展植树活动，五年级有243人，六年级有257人，平均每人植4棵树．他们一共了多少棵树？
<gadget id="calculator">243 + 257</gadget>
<output>500</output>

<gadget id="calculator">500 * 4</gadget>
<output>2_000</output>

<result>2_000</result>