If adding 18 ml of a laundry detergent to 10 liters of water has the best effect, then add this laundry detergent to 120 liters of water, to achieve the best effect, how many ml should be added?
如果在10升水里加入18毫升的一种洗衣液效果最好，那么在120升水里加入这种洗衣液，要使效果最好，请问要加入多少毫升．
<gadget id="calculator">18 * 120</gadget>
<output>2_160</output>

<gadget id="calculator">2_160 / 10</gadget>
<output>216</output>

<result>216</result>