218. To and from work. If a person walks to work and takes transportation back, the total travel time is one and a half hours. If he takes transportation both ways, the entire journey takes him 30 minutes. How much time will the person spend on the road if he walks to and from work?
218. If a person twice travels the route to work and back using the first method, then in doing so, he will twice travel the distance between home and work by transport and twice walk it, spending a total of 3 hours. Therefore, he can walk to work and back in $3-\frac{1}{2}=2 \frac{1}{2}$ hours.