Aunt Li bought 3 kilograms of apples and 4 kilograms of oranges for a total of 27.3 yuan. She only remembered that the price of each kilogram of apples was 3.5 yuan. How much is a kilogram of oranges? (solution by equation)
李阿姨买了3千克苹果和4千克桔子，共花了27.3元，她只记得每千克苹果的价格是3.5元，每千克桔子是多少元？(用方程解)
<gadget id="calculator">3.5 * 3</gadget>
<output>10.5</output>

<gadget id="calculator">27.3 - 10.5</gadget>
<output>16.8</output>

<gadget id="calculator">16.8 / 4</gadget>
<output>4.2</output>

<result>4.2</result>