The students actively participated in the school children's palace activities. Among them, there are 18 people participating in the robot group, 12 people in the aviation model group are 3 times less than the robot group, and the jigsaw technology group is exactly 3 times the aircraft model group. How many people participated in the jigsaw puzzle technology group?
同学们积极参加学校少年宫活动．其中参加机器人小组的有18人，航空模型小组的人数比机器人小组的3倍少12人，七巧板科技小组的人数正好是航空模型小组的3倍．参加七巧板科技小组的一共有多少人？
<gadget id="calculator">18 * 3</gadget>
<output>54</output>

<gadget id="calculator">54 - 12</gadget>
<output>42</output>

<gadget id="calculator">42 * 3</gadget>
<output>126</output>

<result>126</result>