bought a doll for 9.90 yuan and a notebook for 2.50 yuan. How much did I spend in total?
我买了一个布娃娃9.90元，又买了一个笔记本2.50元，一共用了多少元？
<gadget id="calculator">9.9 + 2.5</gadget>
<output>12.4</output>

<result>12.4</result>