A pencil case costs 11.40 yuan, and a pen costs 6.80 yuan. Xiaohua brought 30 yuan and bought a pencil case and a pen. How much money is left?
一个文具盒11.40元，一枝钢笔6.80元，小华带了30元钱，买了一个文具盒和一枝钢笔，还剩下多少钱？
<gadget id="calculator">30 - 11.4 - 6.8</gadget>
<output>11.8</output>

<result>11.8</result>