A certain school conducts military training, the first time it uses 120 rounds of bullets, the second time it uses three times the amount of the first time, and the third time it uses 240 rounds of bullets. How many bullets are used on average each time?
某校进行军事训练，第一次用子弹120发，第二次用的是第一次的3倍，第三次用子弹240发．平均每次用子弹多少发？
<gadget id="calculator">120 * 3</gadget>
<output>360</output>

<gadget id="calculator">120 + 360 + 240</gadget>
<output>720</output>

<gadget id="calculator">720 / 3</gadget>
<output>240</output>

<result>240</result>