Xiao Ming buys 3 books at Xinhua Bookstore, all of which have different prices. Among them, the lowest price is 4 yuan, and the highest price is 9 yuan. What is the total price of Xiao Ming’s three books?
小明到新华书店买了3本书，价格都不相同，其中价格最低的一本为4元钱，价格最高的一本为9元钱，小明买3本书的总价钱可能是多少元
<gadget id="calculator">4 + 6 + 9</gadget>
<output>19</output>

<result>19</result>