Mom bought 14.5 kilograms of radishes in the supermarket, paid 30 yuan, got back 3.9 yuan, how much is it per kilogram of radishes?
妈妈在超市买了14.5千克萝卜，付款30元，找回3.9元，每千克萝卜多少元？
<gadget id="calculator">30 - 3.9</gadget>
<output>26.1</output>

<gadget id="calculator">26.1 / 14.5</gadget>
<output>1.8</output>

<result>1.8</result>