The Arbor Day is coming, and the fifth and sixth grade students of Dongfeng Primary School participated in a tree planting activity. The sixth grade students planted 150 trees, and the fifth grade students planted 20% less trees than the sixth grade students. How many trees were planted in the fifth and sixth grades?
植树节快到了，东风小学五、六年级的学生参加了一次植树活动．六年级学生植树150棵，五年级学生植树比六年级少20%，五、六年级共植树多少棵？
<gadget id="calculator">20 / 100</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">1 - (1/5)</gadget>
<output>4/5 = around 0.8</output>

<gadget id="calculator">150 * (4/5)</gadget>
<output>120</output>

<gadget id="calculator">150 + 120</gadget>
<output>270</output>

<result>270</result>