Xiaohong takes 50 yuan to buy a racket and a box of watercolor pens. Knowing that each racket is 23 yuan and 50 cents, and each box of watercolor pens is 10.8 yuan, how much should I get back?
小红拿50元钱买一支球拍和一盒水彩笔，已知每支球拍23元5角，每盒水彩笔10.8元，应找回多少元？
<gadget id="calculator">50 - 24.3</gadget>
<output>25.7</output>

<result>25.7</result>