On the Arbor Day on March 12, the third-grade students planted 317 trees, 185 fewer than the fourth-grade students. How many trees will the fourth grade students plant?
3月12日植树节那天，三年级同学植树317棵，比四年级同学少植185棵．四年级同学植树多少棵？
<gadget id="calculator">317 + 185</gadget>
<output>502</output>

<result>502</result>