8. (5 points) Person A and Person B start from points $A$ and $B$ respectively at the same time and walk towards each other. Person A's speed is three times that of Person B. After 60 minutes, they meet. Then, Person A's speed is reduced to half of the original speed, while Person B's speed remains unchanged, and both continue to walk. When Person A reaches point $B$, how many more minutes will it take for Person B to reach point $A$?
【Solution】Solution: Let the speed of person B be $x$ meters/minute, then the speed of person A is $3 x$ meters/minute. The time for person A to reach point $B$ after meeting: $60 x \div(3 x \div 2)$,
$$
\begin{array}{l}
=60 x \div 1.5 x, \\
=40 \text { (minutes); }
\end{array}
$$

The time for person B to reach point $A$ after meeting: $(60 \times 3 x) \div x$,
$$
\begin{array}{l}
=180 x \div x, \\
=180 \text { (minutes); } \\
180-40=140 \text { (minutes); }
\end{array}
$$

Answer: When person A reaches point $B$, it will take another 140 minutes for person B to reach point $A$.
The answer is: 140.