The school organized tree planting activities. A total of 86 trees were planted in the third grade, 258 in the fifth grade, and 40 trees were twice as many in the fourth grade as in the third grade. How many trees were planted in the third and fourth grades?
学校组织植树活动，三年级一共栽树86棵，五年级栽树258棵，四年级栽的棵树比三年级的2倍少40棵．三、四年级一共栽多少棵？
<gadget id="calculator">86 * 2</gadget>
<output>172</output>

<gadget id="calculator">172 - 40</gadget>
<output>132</output>

<gadget id="calculator">132 + 86</gadget>
<output>218</output>

<result>218</result>