A measurement team stood a 3-meter-long bamboo pole upright on the ground and measured the shadow length as 1.2 meters. At the same time, it measured the shadow length of a water tower as 7.2 meters. How many meters is the height of this water tower?
某测量小组把一根长3米的竹竿直立在地上，测得影长为1.2米，同时测得一水塔的影长为7.2米，这座水塔的高是多少米？
<gadget id="calculator">3 * 7.2</gadget>
<output>21.6</output>

<gadget id="calculator">21.6 / 1.2</gadget>
<output>18</output>

<result>18</result>