The distance between two buildings is 60 meters. Trees are planted on both sides of the path between the two buildings. Plant one tree every 5 meters. How many trees are planted in total?
两座楼房之间相距60米，在两楼之间的小路两旁栽树，每隔5米栽一棵，一共栽多少棵．
<gadget id="calculator">60 / 5</gadget>
<output>12</output>

<gadget id="calculator">12 - 1</gadget>
<output>11</output>

<gadget id="calculator">11 * 2</gadget>
<output>22</output>

<result>22</result>