13. Two cleaning vehicles, A and B, are tasked with cleaning the road between East City and West City. Vehicle A alone would take 10 hours to clean the road, while Vehicle B alone would take 15 hours. The two vehicles start from East City and West City respectively, heading towards each other. When they meet, Vehicle A has cleaned 12 kilometers more than Vehicle B. How far apart are East City and West City?
13. Two cleaning vehicles, A and B, are tasked with cleaning the road between East and West cities. Vehicle A alone can complete the cleaning in 10 hours, and vehicle B alone can complete it in 15 hours. Both vehicles start from East and West cities respectively and move towards each other. When they meet, vehicle A has cleaned 12 kilometers more than vehicle B. What is the distance between East and West cities?
【Solution】According to the problem, we have: the speed of vehicle A is: $\frac{1}{10}$, the speed of vehicle B is: $\frac{1}{15}$,
$$
\begin{array}{l} 
1 \div\left(\frac{1}{10}+\frac{1}{15}\right) \\
= 1 \div \frac{1}{6} \\
= 1 \times 6 \\
= 6 \text { (hours); } \\
12 \div\left(\frac{1}{10} \times 6-\frac{1}{15} \times 6\right) \\
= 12 \div\left(\frac{6}{10}-\frac{6}{15}\right) \\
= 12 \div \frac{1}{5} \\
= 12 \times 5 \\
= 60 \text { (kilometers); }
\end{array}
$$

Answer: The distance between the two cities is 60 kilometers.