In order to encourage residents to save water, a certain city stipulates that if the monthly water consumption is less than 10 tons, the water price is 1.8 yuan per ton; for the part exceeding 10 tons, the water price is 2.4 yuan per ton. Xiaoxiong's family uses 18 tons of water in October. How much is the water fee?
为鼓励居民节约用水，某市规定：每月用水量在10吨以内的，水价是每吨1.8元；超过10吨的部分，水价是每吨2.4元．小雄家十月分用水18吨，应缴水费多少元？
<gadget id="calculator">10 * 1.8</gadget>
<output>18</output>

<gadget id="calculator">18 - 10</gadget>
<output>8</output>

<gadget id="calculator">8 * 2.4</gadget>
<output>19.2</output>

<gadget id="calculator">18 + 19.2</gadget>
<output>37.2</output>

<result>37.2</result>