Aunt Wang bought 6 kilograms of apples for 29.4 yuan, and Aunt Bai bought 5 kilograms of apples for 25.5 yuan. Who buys the most expensive apples? How expensive is it?
王阿姨买6千克苹果用去29.4元，柏阿姨买5千克苹果用去25.5元，谁买的苹果单价贵？贵多少？
<gadget id="calculator">25.5 / 5</gadget>
<output>5.1</output>

<gadget id="calculator">29.4 / 6</gadget>
<output>4.9</output>

<gadget id="calculator">5.1 - 4.9</gadget>
<output>0.2</output>

<result>0.2</result>