The circumference of a round lake is 108 meters. Plant a willow tree every 12 meters around the lake, and then plant three peach trees at equal distances between the two willow trees. How many willow trees and peach trees can be planted in this way?
圆湖周长108米，在湖边每隔12米种植一棵柳树，再在两棵柳树之问等距离地种3棵桃树，这样可种柳树和桃树共多少棵．
<gadget id="calculator">108 / 12</gadget>
<output>9</output>

<gadget id="calculator">3 * 9</gadget>
<output>27</output>

<gadget id="calculator">9 + 27</gadget>
<output>36</output>

<result>36</result>