The construction team installed the sewer. It was planned to install 48 meters per day and complete it in 15 days. In order to catch up with the construction period, it was actually completed 3 days earlier than planned. How many meters are actually installed per day more than planned? (Solve with ratio)
施工队安装下水道，计划每天安装48米，15天完成，为了赶工期，实际比计划提前了3天完成．实际每天比计划多安装多少米？(用比例解)
<gadget id="calculator">48 * 15</gadget>
<output>720</output>

<gadget id="calculator">3 * 48</gadget>
<output>144</output>

<gadget id="calculator">15 * 48</gadget>
<output>720</output>

<gadget id="calculator">144 - 720</gadget>
<output>-576</output>

<gadget id="calculator">720 + (-576)</gadget>
<output>144</output>

<gadget id="calculator">15 - 3</gadget>
<output>12</output>

<gadget id="calculator">144 / 12</gadget>
<output>12</output>

<result>12</result>