Uncle Li fills up 30 liters of gasoline at the gas station and goes to the Botanical Garden, which is 242 kilometers away from the gas station. If he travels 11 kilometers per liter of gasoline, he arrives at the destination and returns. Do he need to refuel on the way? If necessary, at least how many liters should be added?
李叔叔在加油站加了30升汽油后，去距离加油站242千米的植物园游园，如果每升汽油行驶11千米，他到达目的地后再返回，途中需要加油吗？如果需要，至少还要加多少升才够？
<gadget id="calculator">2 / 11</gadget>
<output>2/11 = around 0.181818</output>

<gadget id="calculator">242 * (2/11)</gadget>
<output>44</output>

<gadget id="calculator">44 - 30</gadget>
<output>14</output>

<result>14</result>