Mom bought a towel for 4.5 yuan for 30 yuan, and a bag of washing powder for 5.80 yuan. How much should I get back?
妈妈用30元买了一条毛巾4.5元，一袋洗衣粉5.80元，应找回多少元？
<gadget id="calculator">30 - 10.3</gadget>
<output>19.7</output>

<result>19.7</result>