Xiaoming has 4.2 yuan. After giving Xiaohua 0.5 yuan, it is 0.3 yuan more than Xiaohua. How much money does Xiaohua have.
小明有4.2元钱，给小华0.5元钱后还比小华多0.3元，小华原有多少元钱．
<gadget id="calculator">4.2 - 0.5 - 0.3 - 0.5</gadget>
<output>2.9</output>

<result>2.9</result>