Zhang Yang buys four books with 50 yuan (the smallest unit of pricing for a book is a jiao). When I went home and calculated, the "Dictionary for Solving Mathematical Olympiad" took up exactly half of the money, and the remaining half (3/20) was used to buy "Chinese Dictionary", (5/23) was used to buy "English-Chinese Dictionary", How much money did he have left in the end?
张阳拿着50元钱买四本书(书的定价最小单位是角)．回家一算，《数学奥林匹克解题辞典》恰好占用去的钱的一半，其余一半里有(3/20)用于买《汉语字典》，(5/23)用于买《英汉字典》，他最后剩下了多少元．
<gadget id="calculator">50 - 46</gadget>
<output>4</output>

<result>4</result>