17. (6 points) Xiaoming and his father went to Grandma's house, and they spent a total of 162 yuan on two train tickets. Xiaoming's train ticket price is half of his father's. How much is Xiaoming's train ticket price in yuan?
【Answer】Solution: $162 \div(1+2)$
$$
\begin{array}{l}
=162 \div 3 \\
=54 \text { (yuan) }
\end{array}
$$

Answer: The price of Xiaoming's train ticket is 54 yuan.