Li Mei bought 4.5 kilograms of grapefruit in the supermarket, paid the salesperson a RMB 50 note, and got back 34.7 yuan. How much is a kilogram of grapefruit?
李梅在超市买了4.5千克柚子，付给售货员一张50元的人民币，找回34.7元，每千克柚子多少钱？
<gadget id="calculator">50 - 34.7</gadget>
<output>15.3</output>

<gadget id="calculator">15.3 / 4.5</gadget>
<output>3.4</output>

<result>3.4</result>